A - Encyclopaedia

A
A (physics)
a cappella
A Coruña (city)
A level
a posteriori
a priori
Açores
a/c
Aachen
Aalto, Alvar (Hugo Alvar Henrik)
aardvark
aardwolf
AAS
abacus
Abadan
abalone
Abba (music)
Abbado, Claudio
Abbas I, the Great
Abbasid dynasty
abbey
Abbey Theatre
Abbott and Costello
abbreviation
Abd al-Hamid II
Abd al-Malik Ibn Marwan
abdication crisis
abdomen
Abdullah I, Abdullah ibn Hussein
Abdullah II, Abdullah ibn Hussein
Abdullah, Sheikh Muhammad
Abe, Shinzo
Abel
Abel, John Jacob
Abelard, Peter
Aberdeen
Aberdeen, George Hamilton Gordon, 4th Earl of Aberdeen
aberration of starlight
aberration, optical
Aberystwyth
Abidjan
abiotic factor
Abkhazia
ablation
ablution
abolitionism
abominable snowman
Aboriginal art
aborigine
abortion
Aboukir Bay, Battle of
Abraham
Abraham, Plains of
abrasion (earth science)
abrasive
Abruzzi
Abruzzo
abscess
abscissa
abscissin
abscission
absolute value
absolute zero
absolution
absolutism (government)
absorption
abstract art
abstract expressionism
Absurd, Theatre of the
Abu Bakr
Abu Dhabi
Abu Simbel
Abu Zabi
Abuja
abyssal plain
abyssal zone
Abyssinia
AC
acacia
Academy Award
acanthus
Acapulco
ACAS
accelerando
accelerated freeze drying
acceleration
accelerator
accent (music)
accent (spoken)
accent (written)
Access
access time
accession
accessory
accidental
acclimation
accommodation
accompaniment
accomplice
accordion
accountant
accounting
Accra
accumulator (computing)
accumulator (physics)
accuracy
acetaldehyde
acetate
acetic acid
acetone
acetylcholine
acetylene
Achaea
Achaean League
Achebe, Chinua
achene
Achernar
Achilles
Achilles tendon
achromatic lens
acid
acid rain
acid salt
Ackroyd, Peter
aclinic line
acne
aconite
acorn
acoustic
acoustics (physics)
acquired character
acquired immune deficiency syndrome
acquittal
Acre
acre
Acrobat (computing)
acronym (language)
acropolis
acrostic
Acrux
acrylic fibre
acrylic paint
act
act of Congress
act of God
act of Parliament
actinide
actinium
action (law)
action art
action painting
action potential
ActionAid
Actium, Battle of
activation energy
active transport
active voice
active window
ActiveX
Acts of the Apostles
actuary
acupuncture
acute
acute angle
Ad Dakhla
Ad Dawhah
Ada
adagio
Adam (architects)
Adam (biblical)
Adams, Gerry
Adams, John
Adams, John Couch
Adams, John Quincy
Adams, Richard (George)
Adams, Samuel
Adamson, Robert
Adana
adaptation
adaptive radiation
Adcock, (Kareen) Fleur
Addams, Charles Samuel
adder (snake)
addiction
Addis Ababa
Addison, Joseph
addition
addition polymerization
addition reaction
additive
address book
Adelaide (city)
Aden
Adenauer, Konrad
adenoids
adenosine triphosphate
ADH
adhan
adhesive
adiabatic
Adige
adipose tissue
Adirondacks
Adis Abeba
adjectival clause
adjectival phrase
adjective
adjournment
Adler, Alfred
administrative law
admiral butterfly (species)
Admiralty Islands
Admiralty, Board of the
adobe
adolescence
Adonis (mythology)
adoption
Adorno, Theodor Wiesengrund
ADP
adrenal gland
adrenaline
Adrian IV
Adriatic Sea
ADSL
adsorption
adult education
adultery
Advent
Adventist
adventure novel
adverb
adverbial clause
adverbial phrase
advertising
advertising (computer)
Advertising Standards Authority
Advisory, Conciliation, and Arbitration Service
Adygeya
Aegean art
Aegean Islands
Aegean Sea
Aelfric
Aeneas
Aeolian Islands
aerial
aerial oxidation
aerobic
aerobic respiration
aerobics
aerodynamics
aerogel
aeronautics
aeroplane
aerosol
Aeschylus
Aesculapius
Aesop
Aesthetic Movement
aestheticism
aesthetics
aestivation
affidavit
affinity (chemistry)
affinity (law)
affirmative action
affirmative action, USA
affix
afforestation
Afghan hound
Afghan Wars
Afghanistan
Africa
Africa, Horn of
Africa, the scramble for
African art
African literature
African music
African National Congress
African nationalism
African Union
African violet
Afrikaans language
Afrikaner
Afro-Asiatic language
Afro-Caribbean
afterbirth
afterburning
afterimage
afterlife
Aga Khan IV, (Karim)
Agadir
Agamemnon
agamid
agar
agaric
Agassi, Andre Kirk
Agassiz, (Jean) Louis Rodolphe
agate
agave
Age Concern
ageing
ageism
Agenda 21
Agent Orange
aggression (biology)
Agincourt, Battle of
agitprop
agnosticism
agoraphobia
agouti
Agra
agrarian revolution
agreement
agribusiness
Agricola, Gnaeus Julius
agricultural revolution
agriculture
agriculture, 19th-century British
agriculture, medieval
Agrippa, Marcus Vipsanius
agronomy
AH
Ahaggar
Ahern, Bertie Patrick Bartholemew
ahimsa
Ahmad Shah Durrani
Ahmadabad
Ahriman
Ahura Mazda
Ahvaz
Ahvenanmaa
AI
aid
Aidan, St
AIDS
Aiken, Howard Hathaway
ailanthus
Ainu
air (chemistry)
air mass
air pollution
air resistance
air sac
air transport
aircraft
aircraft carrier
Airedale terrier
airlock
airship
Aix-en-Provence
Aix-la-Chapelle
Ajaccio
Ajanta
Ajax
Ajman
Ajmer
ajolote
Akal Takht
Akbar, Jalal ud-Din Muhammad
Akhand Path
Akhenaton
Akhetaton
akhirah
Akhmatova, Anna
Akihito
Akkad
Akko
Akram, Wasim
Akron
Aksum
Al Basrah
Al Madinah
Al Manamah
Al Mukalla
al-
Al-Quds
Alabama
alabaster
Alamein, El, battles of
Alamo, the
Alanbrooke, Alan Francis Brooke
Alania
Alaric
Alaska
Alaskan malamute
Alba
Alban, St
Albania
Albanian
Albany (New York State)
albatross
albedo
Albee, Edward (Franklin)
Albert II, Crown Prince
Albert, Lake
Albert, Prince Consort
Alberta
Alberti, Leon Battista
Albigenses
albinism
Albion
albumin
Albuquerque
Albuquerque, Afonso de
alchemy
Alcibiades
Alcock, John William
alcohol (chemistry)
alcohol, effects
alcoholic beverage
Alcoholics Anonymous
alcoholism
Alcott, Louisa May
Alcuin
Aldebaran
Aldeburgh
aldehyde
alder
Aldermaston
Alderney
Aldershot
Aldiss, Brian W(ilson)
Aldus PageMaker
aleatory music
Alemanni
Aleppo
Aletsch
Aleutian Islands
Alexander (III) the Great
Alexander I (of Russia)
Alexander I (of Scotland)
Alexander I, Karageorgevich (of Yugoslavia)
Alexander II (of Russia)
Alexander II (of Scotland)
Alexander III (of Russia)
Alexander III (of Scotland)
Alexander III (pope)
Alexander Nevski, St
Alexander Severus
Alexander technique
Alexander VI (pope)
Alexander, Harold Rupert Leofric George
Alexandra Feodorovna (tsarina)
Alexandria (Egypt)
Alexandria, Library of
Alexandria, school of
Alexius I, Comnenus
Alexius III, Angelos
Alexius IV, Angelos
alfalfa
Alfonsín Foulkes, Raúl Ricardo
Alfonso (X), the Wise
Alfonso (XI), the Avenger
Alfonso VII
Alfonso XII
Alfonso XIII
Alfred the Great
algae
Algarve
algebra
Algeciras
Alger
Algeria
Algiers
Algiers, Battle of
Algol
Algonquin
algorithm
Ali
Ali Pasha, Mehmed Emin
Ali, Muhammad
alibi
Alicante (city)
alien
alienation
alimentary canal
alimony
aliphatic compound
alkali
alkali metal
alkaline-earth metal
alkaloid
alkane
alkene
alkyne
All Saints' Day
All Souls' Day
Allah
Allahabad
Allegheny Mountains
allegory
allegory (art)
allegretto
allegro
allele
Allen, Bog of
Allen, Woody
Allenby, Edmund Henry Hynman
Allende (Gossens), Salvador
allergy
Alliance, the
Allied Coordination Committee
Allies, the
alligator
alliteration
allium
allotropy
alloy
allspice
alluvial deposit
alluvium
Alma-Tadema, Lawrence
Almaty (city)
Almería
Almohad
almond
Almoravid
aloe
alpaca
alpha and omega
Alpha Centauri
alpha particle
alphabet
alphanumeric data
Alps
Alps, Australian
Alps, Southern
Alsace
Alsace-Lorraine
Alsatian
Altai (republic)
Altai Mountains
Altair
Altamira (caves)
Altamira (city)
altar
altarpiece
Altay
Altdorfer, Albrecht
alternate angles
alternating current
alternation of generations
alternative medicine
alternator
Althing
altimeter
altiplano
altitude (height)
Altman, Robert
alto
altruism (biology)
ALU
alum
alumina
aluminium
Alva, Ferdinand Alvarez de Toledo
Alvarez Quintero, Serafin (1871–1938) and Joaquin (1873–1944)
alveolus
Alzheimer's disease
AM
Amal
Amalfi
amalgam
amanita
Amar Das
Amarillo
Amazon (river)
Amazon (warrior)
Amazon.com
Amazonia
Amazonian Indian
ambassador
amber
ambergris
ambiguity
Ambrose, Curtly Elconn Lynwall
Amenhotep III
America
America Online
America's Cup
American Arbitration Service
American Civil War
American Federation of Labor
American football
American Independence, War of
American Indian art
American literature
American Revolution
American Samoa
americium
amethyst
Amhara
Amida Buddha
Amidah
amide
Amiens
Amies, (Edwin) Hardy
Amin (Dada), Idi
amine
amino acid
Amis, Kingsley (William)
Amis, Martin Louis
Amman
ammeter
Ammon
ammonia
ammonite
ammonium nitrate
amnesia
amnesty
Amnesty International
amniocentesis
amoeba
Amoy
amp
ampere
amphetamine
amphibian
amphitheatre
amplifier
amplitude (physics)
amplitude modulation
amrit
Amrit Sanskar
Amritsar
Amritsar Massacre
Amsterdam
Amu Darya
Amundsen, Roald Engelbrecht Gravning
Amur
amyl alcohol
amylase
Anabaptist
anabolic steroid
anabolism
anachronism
anaconda
anaemia
anaerobic
anaerobic respiration
anaesthetic
analgesic
analogous
analogue
analogue computer
analogue signal
analogue-to-digital converter
analogy
analysis (communication)
analysis (mathematics)
analytical chemistry
analytical geometry
Anandpur Sahib
anarchism
Anatolia
anatomy
anatta
ANC
ancestor worship
Anchorage
anchovy
Ancona (town)
Andalusia
Andaman and Nicobar Islands
Andaman Islands
andante
Andean Indian
Andersen, Hans Christian
Anderson shelter
Anderson, Elizabeth Garrett
Andes
andesite
Andhra Pradesh
Andorra
Andorra la Vella
Andrea del Sarto
Andreotti, Giulio
Andrew, Andrew Albert Christian Edward
Andrew, Rob
Andrew, St
Andrews, Julie
androecium
androgen
Andromache
Andromeda (astronomy)
Andromeda galaxy
Andropov, Yuri
anecdote
anemometer
anemone
anemophily
aneroid barometer
aneurysm
Angad
angel (religion)
angel dust
Angel Falls
angelfish
angelica
Angelico, Fra
Angelou, Maya
Angers
Angevin
angina
angiosperm
Angkor
Angle
angle
angle of declination
angle of reflection
angler
Anglesey (Wales)
Anglican communion
Anglicanism
angling
Anglo–Irish relations
Anglo-American War
Anglo-Catholicism
Anglo-Irish Agreement
Anglo-Irish Treaty
Anglo-Irish War
Anglo-Saxon
Anglo-Saxon art
Anglo-Saxon Chronicle
Anglo-Saxon language
Angola
Angora
Angry Young Men
angstrom
Anguilla
Anhui
anhydride
anhydrous
anicca
aniline
animal
animal cell
animal liberation
animation
animism
anion
anise
Anjou
Ankara
Annaba
Annam
Annamese
Annan, Kofi
Annapolis
Annapurna
Anne
Anne of Austria
Anne of Cleves
Anne of Denmark
Anne, Anne Elizabeth Alice Louise
annealing
annelid
annihilation
anno Domini
anno hegirae
annual percentage rate
annual plant
annual report
annual rings
Annunciation
anode
anodizing
anointing of the sick
anorexia
Anouilh, Jean
Anselm, St
Anshan
ant
ant lion
antacid
antagonistic muscles
Antall, József
Antalya
Antananarivo
Antarctic Circle
Antarctic Ocean
Antarctic Territory, Australian
Antarctic Territory, British
Antarctic Treaty
Antarctica
Antares
anteater
antecedent (grammar)
antelope
antenatal
antenna (communications)
antenna (zoology)
anthem
anther
antheridium
antherozoid
Anthony, St
anthracite
anthrax
anthropoid
anthropology
anthropomorphism
anti-aliasing
anti-art
Anti-Corn Law League
anti-emetic
anti-oxidant
anti-Semitism
antibiotic
antibody
Antichrist
anticlimax
anticline
anticoagulant
anticyclone
antidepressant
antidiuretic hormone
antifreeze
antigen
Antigone
Antigua and Barbuda
antihistamine
Antilles
antimatter
antimony
antinuclear movement
Antioch (Syria)
Antiochus (III) the Great
Antiochus I
Antiochus IV (of Syria)
Antiochus VII
Antiochus XIII
antiparticle
antiphony
antipodes
antipope
antipyretic
antiseptic
antithesis
antitussive
antivivisection
antler
Antonello da Messina
Antonine Wall
Antoninus Pius, Titus Aurelius Fulvus
Antonioni, Michelangelo
antonym
Antrim (county)
Antwerp (town)
Antwerpen
Anubis
anus
anxiety
Anyang
Anzac
Anzio
Anzio, Battle of
AOL
Aoraki
aorta
Aouita, Said
Apache
apartheid
apatite
apatosaurus
ape
Apelles
Apennines
aperture
aphasia
aphelion
aphid
aphorism
aphrodisiac
Aphrodite
Apia
Apis
Apo, Mount
Apocrypha
apogee
Apollinaire, Guillaume
Apollo
Apollo asteroid
Apollonius of Perga
Apollonius of Rhodes
apostle
Apostles' Creed
apostolic succession
apostrophe (grammar)
apothecaries' weights
Appalachian Mountains
apparent depth
appeal
appeasement
appendicitis
appendix (anatomy)
Appennino
apple
Appleton layer
application (computing)
appliqué
Appomattox Court House
apposition
appropriate technology
approximation
APR
apricot
Apuleius, Lucius
Apulia
Aqaba, Gulf of
Aqtöbe (city)
aquaculture
aqualung
aquamarine
aquaplaning
aquarium
Aquarius
aquatic insect
aquatint
aqueduct
aqueous humour
aquifer
Aquila
Aquinas, St Thomas
Aquino, (Maria) Corazon
Aquitaine
Ar Riyad
arête
Arab
Arab Common Market
Arab Emirates
Arab League
Arab Maghreb Union
Arab Monetary Fund
Arab–Israeli Wars
arabesque (art)
arabesque (dance)
Arabia
Arabian Sea
Arabic language
arable farming
arachnid
Arafat, Yassir
Arafura Sea
Aragón (autonomous community)
Aragon, Louis
Arakan
Aral Sea
Aramaic language
Aran Islands
Arapaho
Ararat, Mount
Araucanian Indian
araucaria
Arawak
Arbil
arbitrageur
arbitration
arbor vitae
arboretum
Arbroath
Arbus, Diane
arc
Arc de Triomphe
arc lamp
arc minute
arcade
Arcadia
arch (architecture)
arch (earth science)
Archaea
Archaean
archaeology
archaeopteryx
Archangel (port)
archbishop
archdeacon
archery
archetype
Archimedes (mathematician)
Archimedes screw
Archimedes' principle
Archipel de la Société
Archipel des Tuamotu
archipelago
Archipelago de las Perlas
Archipenko, Alexander
architecture
archon
Arcimboldo, Giuseppe
Arctic Circle
Arctic Ocean
Arctic, the
Arcturus
Ardas
Ardennes (plateau)
are
area
areca
Arecibo
Arendt, Hannah
Arequipa (city)
Ares
Arezzo (town)
argali
Argand diagram
Argentina
argon
argonaut
Argonauts
Argos
Argus
Argyll and Bute
Ariège (river)
aria (music)
Ariadne
Ariane rocket
Arianism
Arica
arid region
Aries
Ariosto, Ludovico
Aristarchus of Samos
Aristide, Jean-Bertrand
Aristides
aristocracy
Aristophanes
Aristotle
arithmetic
arithmetic and logic unit
arithmetic mean
arithmetic progression
Arizona
Arjan
Ark of the Covenant
Arkansas
Arkhangelsk
Arkwright, Richard
Arles
Arlington
Armada
armadillo
Armageddon
Armagh (city)
Armagh (county)
Armani, Giorgio
armature
armature (sculpture)
armed forces
Armenia
Armenian
Armenian Church
Armenian language
Armenian massacres
Arminius
Arminius, Jacobus
armistice
Armistice Day
Armitage, Simon
armour
arms control
arms trade
Armstrong, Lance
Armstrong, Louis
Armstrong, Neil Alden
Arnhem Land
Arnhem, Battle of
Arnim, Ludwig Achim von
Arno
Arnold, Benedict
Arnold, Malcolm Henry
Arnold, Matthew
Arnold, Thomas
aromatherapy
aromatic compound
Arp, Hans
ARPANET
arpeggio
Arran
Arras
arrest
Arrhenius, Svante August
arrhythmia
arrowroot
Arsacid dynasty
arsenic
arson
art
art brut
art deco
art for art's sake
art nouveau
Artaud, Antonin
artefact
Artemis
arteriosclerosis
artery
artesian well
arthritis
arthropod
Arthur
arti
artichoke
article (grammar)
article (piece of writing)
artificial insemination
artificial intelligence
artificial respiration
artificial selection
artillery
Arts and Crafts Movement
Arts Councils
Aruba
arum
Arunachal Pradesh
Arundel
Aryan
Aryan languages
AS level
asbestos
Ascension
Ascension Day
asceticism
Ascham, Roger
ASCII
Asclepius
ascorbic acid
Ascot
ASEAN
asepsis
asexual reproduction
ash
Ash Wednesday
Ashanti
Ashcan School
Ashcroft, Peggy
Ashdod
Ashe, Arthur (Robert, Jr)
Ashes, the
Ashford
Ashgabat
Ashikaga
Ashkenazi
Ashkenazy, Vladimir Davidovich
Ashkhabad
Ashley, Laura
Ashmore and Cartier Islands
ashram
ashrama
Ashton, Frederick William Mallandaine
Asia
Asia Minor
Asian Republics, Central
Asimov, Isaac
Asmara
Asoka
asp
asparagus
aspartame
aspect
Aspen
aspen
asphalt
asphodel
asphyxia
aspidistra
aspirin
Asquith, Herbert Henry
ass
Assad, Hafez al
Assam
assassin bug
assassination
assault
assay
assemblage (art)
assembly language
asset
asset stripping
assimilation
Assisi
assisted area
Assisted Places Scheme
assize
Association of Caribbean States
Association of South East Asian Nations
associative operation
assonance
assurance
Assyria
Astaire, Fred
Astana (city)
Astarte
astatine
aster
asterisk
asteroid
asthenosphere
asthma
Asti (town)
astigmatism
Astor
Astrakhan (city)
astrolabe
astrology
astrometry
astronomical unit
astronomy
astrophotography
astrophysics
Asturias (autonomous community)
Asturias, Miguel Ángel
Asunción
asylum, political
asymmetric valley
asymptote
Asyut
Atacama Desert
Atahualpa
Atatürk Dam
Atatürk, Kemal
atavism
ataxia
Athanasian creed
Athanasius, St
atheism
Athelstan
Athena
Athens (Greece)
atheroma
atherosclerosis
Atherton, Michael Andrew
athletics
Athos
Atlanta
Atlantic City
Atlantic Ocean
Atlantic, Battle of the (World War I)
Atlantic, Battle of the (World War II)
Atlantis
Atlas
atlas
Atlas Mountains
atman
atmosphere (earth science)
atmosphere (physics)
atmospheric pressure
atoll
atom
atom, electronic structure of
atomic bomb
atomic clock
atomic energy
atomic mass
atomic mass unit
atomic number
atomic radiation
atomic structure
atomic weight
atomicity
atomizer
Aton
atonality
atonement
Atonement, Day of
ATP
atrium (architecture)
atrophy
atropine
attachment
attempt
Attenborough, David Frederick
Attenborough, Richard Samuel
attention-deficit hyperactivity disorder
Attica
Attila
Attis
Attlee, Clement (Richard)
attorney
Attorney General
attrition
Atwood, Margaret Eleanor
aubergine
Aubrey, John
aubrieta
Auchinleck, Claude John Eyre
Auckland (city)
auction bridge
Aude (river)
Auden, W(ystan) H(ugh)
audience
audit
Audubon, John James
Auerbach, Frank Helmuth
Augean stables
Augsburg
Augsburg, Confession of
augur
Augustan Age
Augustine of Hippo, St
Augustine, St
Augustinian
Augustus
auk
Aung San
Aung San Suu Kyi
Aurangzeb
Aurelian
Aurelius Antoninus
Aurelius, Marcus
Auric, Georges
Auriga
Aurignacian
aurochs
aurora (astronomy)
Aurora (mythology)
Auschwitz
auscultation
Austen, Jane
Austerlitz, Battle of
Austin
Australia
Australian Aboriginal religions
Australian Aborigine
Australian Alps
Australian art
Australian Capital Territory
Australian terrier
Austria
Austrian Succession, War of the
Austro-Hungarian Empire
Austronesian languages
autarky
authenticity
authoritarianism
autism
auto-da-fé
autobiography
autochrome
autoclave
autocracy
autogiro
autoimmunity
autolysis
automatic pilot
automation
automatism (art)
automatism (medicine)
automaton
autonomic nervous system
autonomy
autopsy
autoradiography
autosome
autosuggestion
autotroph
autumn crocus
autumnal equinox
Auvergne
Auxerre
auxiliary verb
auxin
avalanche
Avalokitesvara
Avalon
avant-garde
avatar
Ave Maria
Avebury
Avedon, Richard
avens
average
Averroës
Avery, Milton
AVI
aviation
Avicenna
Aviemore
Avignon
Avila (city)
avocado
avocet
Avogadro's hypothesis
Avogadro's number
avoirdupois
Avon (Northamptonshire, Warwickshire)
AWACS
Awash
Axelrod, Julius
axil
axiom
axis
Axis
axolotl
axon
axonometric projection
Axum
ayatollah
Ayckbourn, Alan
aye-aye
Ayer, A(lfred) J(ules)
Ayers Rock
Ayesha
Aymara
Ayr
azalea
Azerbaijan
Azerbaijan, Iranian
Azeri
Azilian
azimuth
azo dye
Azores
Azov, Sea of
AZT
Aztec
Aztec art