- astronomical year
- astronomy
- astrophile
- astrophotography
- astrophotometry
- astrophysical
- astrophysics
- astrosphere
- astrotourism
- astrotourist
- astroturfing
- astro–
- astute
- astuteness
- astylar
- asunder
- aswarm
- aswirl
- aswoon
- asylee
- asyllabic
- asylum
- asylum seeker
- asymmetric
- asymmetric bars
- asymmetric slow-wave sleep
- asymmetric time
- asymmetric warfare
- asymmetrical warfare
- asymmetry
- asymptomatic
- asymptote
- asymptotic
- asymptotic freedom
- asymptotically
- asynapsis
- asynchronism
- asynchronous
- asynchronous transmission
- asyndetic
- asyndeton
- asynergia
- asynergy
- asyntactic
- asystole
- asˈcetiˌcism
- asˈtronomer
- at
- at a discount
- at a loss
- at a low ebb
- at a premium
- at a sitting
- at a stretch
- at a time
- at a word
- at about
- at all
- at all costs
- at all times
- at any cost
- at any rate
- at arm's length
- at bat
- at bay
- at best
- at bottom
- at close quarters
- at close range
- at cross purposes
- at death's door
- at each other's throats
- at ease
- at every turn
- at face value, take
- at fault
- at first
- at first blush
- at first hand
- at full tilt
- at gunpoint
- at half-mast
- at hand
- at heart
- at home
- at issue
- at it
- at large
- at last
- at law
- at least
- at leisure
- at length
- at liberty
- at loggerheads
- at long last
- at loose ends
- at most
- at odds
- at once
- at one
- at one blow
- at one fell swoop
- at one stroke
- at one time
- at one time or another
- at one's
- at one's best
- at one's convenience
- at one's door
- at one's ease
- at one's fingertips
- at one's leisure
- at one's wit's end
- at one's word
- at pains, be at
- at peace
- at present
- at random
- at rest
- at risk
- at sea
- at second hand
- at sight
- at sixes and sevens
- at someone's
- at someone's beck and call
- at someone's elbow
- at someone's feet, be
- at someone's heels
- at someone's mercy
- at someone's request
- at someone's service
- at stake
- at sword's point
- at that
- at that point
- at that rate
- at that stage
- at the crossroads
- at the drop of a hat
- at the end of one's rope
- at the end of the day
- at the expense of
- at the hand of
- at the helm
- at the last minute
- at the latest
- at the least
- at the mercy of
- at the most
- at the outset
- at the outside
- at the point of
- at the ready
- at the same time
- at the top of one's lungs
- at the wheel
- at the worst
- at this point
- at this rate
- at this stage
- at times
- at variance
- at war
- at will
- at work
- at worst
- at wt
- at-
- at-desk
- at-home
- at-will
- at.
- at. no.
- ataata
- atacamite
- atactic
- ataghan
- ataman
- atamasco lily
- ataractic
- ataraxia
- atavic
- atavism
- atavistic
- ataxia
- ate
- atef-crown
- atelectasis
- atelier
- ateliosis
- atemoya
- atemporal
- atenolol
- athame
- athanasia
- athanor
- atheism
- atheist
- atheistic
- athel tree
- atheling
- athematic
- athenaeum
- atheoretical
- atherectomy
- atherine
- athermancy
- athermanous
- athero-
- atherogenic
- atheroma
- atherosclerosis
- athetosis
- athirst
- athleisure
- athlete
- athlete's foot
- athlete's heart
- athletic
- athletic shoe
- athletic support
- athletically
- athleticism
- athletics
- athodyd
- athonite
- athrill
- athrocyte
- athwart
- athwartships
- atigi
- atilt
- atingle
- atiptoe
- atishoo
- atlantal
- atlantes
- atlas
- atlatl
- atm.
- atman
- atmo-
- atmolysis
- atmometer
- atmometry
- atmophile
- atmosphere
- atmospheric
- atmospheric braking
- atmospheric electricity
- atmospheric engine
- atmospheric perspective
- atmospheric pressure
- atmospheric river
- atmospheric tide
- atmospheric window
- atmospherics
- atmospherium
- atole
- atoll
- atom
- atom smasher
- atom trap
- atom-bomb
- atomic
- atomic age
- atomic bomb
- atomic clock
- atomic cocktail
- atomic energy
- atomic force microscope
- atomic heat
- atomic hydrogen
- atomic mass
- atomic mass unit
- atomic number
- atomic pile
- atomic power
- atomic spectrum
- atomic structure
- atomic theory
- atomic veteran
- atomic volume
- atomic weight
- atomicity
- atomics
- atomism
- atomization
- atomize
- atomizer
- atomy
- atonal
- atonalism
- atonality
- atone
- atonement
- atonic
- atonicity
