- Against the clock
- Agape
- Age limit
- Age of kali
- Ager
- Agglomerate
- Agglomeration
- Aggrandize
- Aggrandizement
- Aggravate
- Aggravating
- Aggravation
- Aggress
- 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
- Air conditioner
- Air strike
- Air-conditioned
- Air-mechanic
- Air-pocket
- Air-pump
- Air-raid
- Airborne
- Aircraft
- Aircrew
- Airing cupboard
- Airline
- Airlock
- Airman
- Airport
- Airship
- Airstrip
- Airtight
- Aisle
- Aiyo
- Ajinomoto
- Alabaster
- Alarm clock
- Albeit
- Alchemist
- Alchemy
- Aleatory
- Alert
- Alfalfa
- Algal
- Algebric
- Algebrical elements
- Algol
- Algolagnia
- Alibi
- Alienable
- Alienated
- Align
- Aliment
- Alkali
- Alkalinity
- All along
- All clear
- All directions
- All in a maze
- All in good time
- All of a sudden
- All one knows
- All others
- All round
- All sorts
- All that
- All the same
- All the while
- All-knowing
- All-prevading
- Allege
- Allegro
- Allergen
- Allocate