argi - auto
- argil
- argillaceous
- argillaceous bottom
- argillaceous sandstone
- argillaceous top
- argillite
- argue
- argument
- aricular iron ore
- arithmetic average
- arm
- arm crane
- arm gear
- arm mixer
- arm of angle
- arm of couple
- arm-saw
- armature
- armoring
- armour
- armour gland
- armour plate
- armour-clad
- armoured
- armoured belt
- armoured cable
- armoured concrete
- armoured conveyor
- armoured flexible conveyor
- armoured hose
- armoured-concrete prop
- armoured-face conveyor
- armouring
- around-the-clock
- around-the-clock work
- arrange
- arrangement
- arrangement of chains
- arrest
- arrester
