- Apprise
- Apprize
- Approachable
- Approbate
- Approbatory
- Approve
- Approving
- April
- Apriori
- Apriorism
- Apropos
- Apse
- Archive
- Archives
- Archivist
- Ardent
- Arduous
- Area manager
- Areal flood
- Aren't
- Argent
- Arguing
- Argumentation
- Arms
- Army corps
- Aroma
- Aromatic
- Arpeggio
- Arrange
- Arrest
- Arrest attention
- Arrhythmic
- Arrived
- Articulation
- Artificial respiration
- Artificialness
- Artist
- Artiste
- Artistic
- Artless
- Arts and part
- Arya race
- As one man
- Asian
- As the crows fly
- As though
- As well
- As yet
- As you sow so you reap
- Ascariasis
- Ascendant
- Askant
- Asked
- Asking
- Aslant
- Asleep
- Aspects
- Aspersion
- Assafoetida
- Assail
- Assam
- Assassinate
- Assault
- Assay
- Assured
- Asthenia
- Astis
- Astonished
- Astraddle
- Astral body
- Astray
- At all costs
- At all times
- At close quarters
- At dawn
- At full pelt
- At full strain
- At hand
- At knife point
- At length
- At will
- Atelophobia
- Atheism
- Atheistic
- Athri
- Athwart
- Atlantic
- Atmosphere
- Atom
- Atomic
- Atomic number
- Attendant
- Attending
- Attentive
- Attestation
- Attractiveness
- Atwitter
- Au courant
- Aunt
- Aureate