- Activity
- Actor
- Acts of god
- Add lustre to
- Add time
- Add up to
- Addable
- Added
- Addendum
- Adder
- Addicted to
- Addiction
- Additive
- Address
- Address book
- Address proof
- Adenoidal
- Adequate
- Admit
- Admittance
- Admitting defeat
- Admonition
- Admonitory
- Adon
- Adonis
- Adopted son
- Adoptionism
- Adorn
- Adrenal
- Adrift
- Adsorption
- Adulate
- Adulation
- Adult
- Adulterate
- Adulterated
- Adulteration
- Advanced
- Advantage
- Aerial navigation
- Aerial torpedo
- Aerial vehicle
- Aero logy
- Aeromancy
- Aeronautic
- Aerosol
- Aesthetically
- Aestivation
- Afebrile
- Affairs
- Affectedly
- Aficionado
- Afield
- Afloat
- Afore
- Aforethought
- Afraid
- Afro
- After all
- After growth
- After image
- After ones own heart
- After thinking
- After-taste
- Aftershave
- Aggressor
- Aggro
- Aghast
- Agile
- Agistment
- Agitate
- Agitprop
- Agnail
- Agnus castus
- Agonisingly
- Agony aunt
- Agony column
- Agrarian
- Agrarianism
- Agreeableness
- Agreement
- Agribusiness
- Agronomy
- Ague
- Ah!
- Ahead
- Aide-de-camp
- Ailing
- Ailurophile
- Ailurophobia
- Aimless
- Ain't
- Airing cupboard
- Airline
- Airlock
- Airman
- Airport
- Airship
- Airstrip
- Airtight