- Alloy
- Allure
- Alluring
- Allusion
- Altered
- Alternately
- Alternating current
- Alternation
- Alternator
- Altitude
- Altruism
- Altruistic
- Alu
- Alumna
- Alumnus
- Alzheimer's disease
- Amalgamation
- Amassed
- Amative
- Amethyst
- Amicably
- Amicue curie
- Amidst
- Amoeba
- An acquatic plant
- An arrow
- An either or situation
- An electuary
- An expiatory spell
- An ignoramous
- An iron hand in a velvet glove
- An ornament
- An ornament for the neck
- Anabasis
- Anatomize
- Anchorman
- Ancient
- Ancient times
- And that
- Andaman island
- Andragogy
- Androecium
- Andrology
- Angst
- Angular
- Angular diameter
- Aniconism
- Animal kingdom
- Animistic
- Anise seed
- Anise seed herb
- Annexe
- Another
- Anothers wife
- Ansi
- Antagonize
- Antarctic
- Ante
- Anvil
- Anticipatory
- Anticyclone
- Antifoundationalism
- Antihero
- Antilogy
- Antimycotic
- Antinational
- Antique
- Apheresis
- Aplasia
- Aplenty
- Apocalyptic
- Apolitical
- Apologue
- Apoplectic
- Apostatize
- Apostrophe
- Apotheosis
- Applicable
- Application window
- Applicator
- Appointed
- Appointed time
- Apposite
- Apposition
- Appraisal
- Appraised
- Appreciation
- Aptitude
- Aptness
- Aqua
- Aquamarine
- Aquaphobia
- Aquarius
- Aquatic
- Aqueous
- Aquifer
- Arabia
- Arabic
- Arak
- Arbitrary