- Abaca
- Aback
- Abet
- Abettoir
- Abhor
- Abide by
- Ability to understand
- Abiotic
- Abjuration
- Able
- Able-bodied
- Ably
- Abrachia
- Abraham
- Abrasive
- Abridgement
- Abroad
- Abrogate
- Abrogation
- abrus precatorius
- Abscess
- Abscission
- Absurdly
- Abundant
- Abuse
- Abusive
- Abyss
- Abyssal
- Acacia adoratissima
- Acacia intsia
- Academia
- Academy
- Acarpous
- Accede
- Accelerate
- Accelerator
- Accompany
- Accomplishing
- According
- According to
- According to ones lights
- According to schedule
- Accoucheuse
- Account
- Account for
- Accountability
- Accountable
- Accounting
- Accounts
- Accoutrements
- Accredit
- Achievement quotient
- Achilles heel
- Aching
- Achy
- Acid test
- Acidity
- Acknowledgement
- Acknowledgment
- Acolyte
- Acoustics
- Acquaintances
- Acquainted
- Acquiescence
- Acquiescent
- Acquire
- Acquired
- Acquired taste
- Acquit oneself well
- Acquitted
- Acreage
- Acrochordon
- Actuality
- Acute-angled cucumber
- Acuteness
- Ad
- Ad interim
- Ad valorem
- Adam's apple
- Adamantly
- Adaptability
- Adhatoda vasica
- Adherent
- Adiabatic
- Adieu
- Adipose
- Aditya
- Adjourn
- Adjutant
- Adoring
- Adornment
- Adroitness
- Adsense
- Adulterant
- Adulterator
- Adulterer
- Adulterress
- Adultery
- Advance
- Advance interest