- Audio-visual aids
- Auditory ossicles
- Augean stables
- Augmentation
- Augur
- Augury
- Aureus
- Auricle
- Auspices
- Autarchy
- Authentically
- Authorative person
- Authorial
- Authorise
- Authoritatively
- Authority
- Authorization
- Authorized
- Autism
- Auto-typography
- Autochthons
- Autocrat
- Autograph
- Automatic dictionary
- Automatic pagination
- Automatism
- Autoradiograph
- Autosomal chromosome
- Autotrophic
- Auxiliary bishop
- Availability
- Available resources
- Avarice
- Avenue
- Averse
- Aviation
- Aviatrix
- Aviculture
- Await
- Awaiting
- Awake to
- Awake to reality
- Awareness
- Awash
- Awful
- Awkward age
- Awl
- Ax
- Axe helve
- Axiom
- Axiomatic
- Axis neutral
- Axle
- Ayodhya
- Azoic
- Aviate
- Aviator
- Avidity
- Avocado
- Avocation
- Avoidable
- Avoidance
- Avoiding
- Avow
- Awaken
- Awakened
- Aware
- Away
- Awed
- Awkwardness
- Awning
- Axis
- Axis major
- Axle-nail
- Ayurvedic medicines
- Azymous
- Agoraphobic
- Avoirdupois
- Adp
- Airily
- Amaranthus
- Antiquary
- Auctor
- A bad pill to swallow
- A bed of roses
- A bird in hand is worth two in the bush
- A bit much
- A blood relative
- A cardinal error
- A dead duck
- A dead luck
- A dear john letter
- A disciple who lodges with his preceptor
- A divine ministrel
- A dogs life
- A dry
- A false alarm
- A fiche
- A fish
- A floating voter