- approved
- appurtenance
- arc cutter
- arch acting
- arch girder
- arch-type
- area adjustment
- argillaceous
- arm
- arm saw
- armature
- arrange
- arresting stop
- arterite rock
- artesian
- artesian discharge
- artificial cooling
- artificial drainage
- arm crane
- armor clamp
- armored car
- armoured
- artesian area
- artesian pressure
- articulate
- articulated arm
- articulated suspension
- artificial abutment
- as cast
- asbestos packing
- asbestos sheet
- asbestos tape
- ascentional motion
- ash stop
- asphalt distributor
- asphaltic
- assembly
- assign
- asbestine
- ascension
- ash cell
- ashy
- asphalt grout
- asphalt injection
- assembly opening
- assistant engine
- assumed elevation
- astatic
- astrogeodetic point
- astronomical azimuth