- arsenic
- articulated shaft
- artificial sample
- artificial variable
- ASCII protocol
- aspect
- assembler program
- assembly language
- assert
- assigned number
- associate element
- associated tensors
- associative storage
- associativity relation
- assumption diagram
- astrophysical
- asymmetric network
- asymmetrical effect
- asymmetrical modem
- asymmetrical transmission
- asymptotic convergence
- asymptotic direction
- asymptotic formula
- asymptotic normality
- asymptotic plane
- asymptotic series
- asymptotic spot
- asymptotic surface
- asymptotically efficient
- asynchronous bus
- asynchronous communications
- asynchronous computer
- asynchronous data
- asynchronous logic
- asynchronous motor
- asynchronous procedure
- asynchronous working
- AT bus
- AT command
- at first
- at infinity
- AT keyboard
- at least
- at once
- at random
- atmospheric chamber
- application context
- application data
- application growth
- application option
- application program
- application server
- application-bundling
- application-process
- approximate continuity
- approximate error
- approximation
- apsidal
- aqueous phase
- arabic cipher
- arbiter
- arbitrarily
- arbitrary constant
- arch camber
- architecture
- archival documents
- archival records
- archive file
- archived items
- arcsine
- area chart
- area fill
- area search
- areal derivative
- areal velocity
- arithmetic addition
- arithmetic calculation
- arithmetic complement
- arithmetic conversion
- arithmetic multiplication
- arithmetic operator
- arithmetic scan
- arithmetic sum
- arithmetic underflow
- arithmetically
- armature
- armature varnish
- armoured glass
- array
- array processing
- array section
- array variable
- arrival process
- arrow style
- arrowheads
- artifact
- artificial brain
- arithmetic circuitry
- arithmetic constant
- arithmetic operation