- Askew
- Asocial
- Asp
- Asparagus
- Aspect
- Asperity
- Aspersions
- Asphodel
- Asphyxiate
- Assamese
- Assassination
- Assaulting
- Assemblage
- Assembly
- Assertive
- Assertively
- Assertiveness
- Assiduity
- Assiduous
- Assiduously
- Assimilate
- Assisting
- Assorted
- Assortment
- Assume
- Assure
- Astaghfirullah
- Asterik
- Asteriods
- Asterisk
- Asterism
- Asteroid
- Asthmatic
- Astigmatism
- Astonishment
- Astound
- Astral
- Astro
- Astrobotany
- Astrolabe
- Astrological
- Astrology
- Astronomer
- Astronomical
- Astrophysics
- Asunder
- Aswamedha
- Asylum
- Asymmetry
- At a snails pace
- At a stretch
- At a tender age
- At all events
- At dead of night
- At first
- At loggerheads
- At peace
- At rest
- At school
- At the drop of a hat
- At the end of the tether
- At the full
- At the sea
- At the wicket
- At work
- At-the-outset
- Ataraxy
- Ataxia
- Athenaeum
- Athletic
- Atmospheric air
- Atomic power
- Atomizer
- Atrium
- Atrocity
- Attache
- Attainability
- Attainable
- Attainment of manhood
- Attempt
- Attentiveness
- Attenuation
- Attested
- Atticism
- Attorney
- Attractive
- Attribution
- Auberge
- Audacious
- Audible
- Audiology
- Audiometer
- Audiovisual
- Auditory
- Augean
- August
- Augustan
- Auld
- Auld lang syne
- Aural