- argental
- armature shaft
- armour plate
- aromatic compound
- artesian basin
- artificial ice
- asbestos chalk
- asbestos fiber
- asbestos stopper
- asbestos twine
- ash coal
- asphalt cake
- asphalt powder
- asphalt slab
- asphaltene
- asphaltic compounds
- asphaltic mastic
- asphaltic sheet
- assay button
- associated gas
- associated sheet
- astatic magnetometer
- astatic pendulum
- astatine
- athwardship bulkhead
- atmospheric agent
- atmospheric column
- atmospheric corrosion
- appraisal
- appreciate
- apron conveyor
- aquadag
- aqualization
- aqueous amulsion
- aralkyl
- aramid
- arborescent structure
- archimedean screw
- areal map
- argentiferous
- arid region
- arm
- armoured glass
- aromatic base
- aromatic derivative
- aromatic lacquer
- aromatic ring
- aromatic water
- arostat process
- artesian spring
- artificial asphalt
- artificial atom
- armour hose
- aromatic series
- aromatization
- arsenical
- arsenite
- arsine
- artificial atmosphere
- artificial climate
- artificial graphite
- artificial lift
- aryl radical
- asbestos cloth
- asbestos covering
- asbestos dish
- asbestos felt
- asbestos insulated
- asbestos joint
- asbestos packing
- asbestos pipe
- asbestos plate
- asbestos sheet
- aseismic district
- ashlar stone
- ashless sediment
- asphalt cement
- asphalt distributor
- asphalt flux
- asphalt residue
- asphaltic cement
- asphaltic paint
- asphaltum oil
- assay crucible
- assembly conveyor
- asbestos board
- asbestos putty
- ash
- ash test
- ashless
- asphalt bottom
- asphalt dust
- asphalt filler
- asphaltoid
- assay furnace
- assayer
- assignment
- associated
- associated mineral
- astian stage