- At one time
- At ones risk
- At ones sweet soil
- At peak
- At play
- At sea
- At sixes and sevens
- At stake
- At the eleventh hour
- At the longest
- At the same time
- At the top of ones voice
- Atone
- Atonement
- Atrocious
- Atrocities
- Atrorcious
- Attaching
- Attachment
- Attachments
- Attacker
- Attain
- Attempt the impossible
- Auctioneer
- Audibility
- Audibleness
- Audibly
- Audit
- Audition
- Auditor
- Aught
- Augmented reality
- August-september
- Augustly
- Aunt
- Aureate
- Aurora
- Auster
- Austere
- Auteur
- Authenticate
- Authentication
- Authorised
- Authoritarianism
- Authoritative
- Authorized person
- Autistic
- Auto index
- Auto-ignition
- Autobiography
- Autodidact
- Automation
- Autonomy
- Autopsy
- Autotype
- Autumn
- Avacado
- Avarise
- Aver
- Average
- Avid
- Avidly
- Aviform
- Axle-tree
- Azolla
- Azure
- Altaltissimo
- Ark
- Astron
- Ataxia, ataxia
- a bag of bones
- A bed roses
- A bird in a golden cage
- A bit
- A black sheep
- A black-leg
- A blank look
- A bull in a china shop
- A bun in the oven
- A capella
- A chorus of thanks
- A cold sweat
- A cubit
- A good number of
- A good or great while
- A good second
- A good sort
- A hard life
- A herb
- A herb conceived as being capable of bringing the dead to life
- A large number
- A late hour
- A long face
- A long gasp
- A long time
- A magnetic personality
- A man of substance
- A man of the people
- A man ofwords
- A medicinal grass