- Ash-coloured
- Ash-pit
- Ashamed
- Ashtray
- Asinine
- Assemblage
- Assembly
- Assertive
- Assertively
- Assertiveness
- Assiduity
- Assiduous
- Assiduously
- Assimilate
- Assisting
- Astro
- Astrobotany
- Astrolabe
- Astrological
- Astrology
- Astronomer
- Astronomical
- Astrophysics
- Asunder
- Aswamedha
- Asylum
- Asymmetry
- At a snails pace
- 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
- Atomizer
- Atrium
- Atrocity
- Attache
- Attainability
- Attainable
- Attainment of manhood
- Attempt
- Auberge
- Audacious
- Audible
- Audiology
- Audiometer
- Audiovisual
- Auditory
- Augean
- August
- Augustan
- Auld
- Auld lang syne
- Authorship
- Auto
- Auto score
- Auto-suggestion
- Autocracy
- Autogenously
- Autolysis
- Automatic
- Automatic check
- Automaton
- Automobile
- Avocado
- Avocation
- Avoidable
- Avoidance
- Avoiding
- Avow
- Awaken
- Awakened
- Aware
- Away
- Awed
- Awkwardness
- Awning
- Adp
- Airily
- A good thing
- A grain of paddy
- A hollow laugh
- A host in himself
- A jam session
- A kings ransom
- A lack all
- A laughing stock
- A lazy susan
- A little water
- Abaddon
- Abandoned
- Abandoned woman
- Abandonment
- Abased
- Abashed
- Abba
- Abbreviation