- amygdaloid structure
- anabolism
- anchor packer
- anchor screw
- anthracolithic system
- anti-cooling
- anticenter
- antichlor
- anticlinal closure
- anticlinal composite
- anticlinal crest
- anticlinal line
- anticlinal range
- anticlinal reservoir
- anticlinal ridge
- anticlinal saddle
- anticlinal structure
- anticlinal theory
- anticontamination clothing
- anticorrosive additive
- antidetonamit fuel
- antienzime
- antifoam
- antifoam agent
- antifogging
- antifouling
- antifreeze
- antifreeze liquid
- antifreeze mixture
- antifreeze solution
- antifreezing
- antifreezing agent
- antifriction metal
- antifroth
- aneroid
- aneroid barometer
- angelica oil
- angstrom unit
- anhydrous
- aniline point
- animal charcoal
- animal haulage
- anisotropy coefficient
- annealing carbon
- annealing ore
- anode coating
- anodic coating
- anodize
- antigelling agent
- antigenic mineral
- antigum inhibitor
- antiknock
- antiknock fuel
- antiknock gasoline
- antiknock property
- antiknock quality
- antiknock value
- antimagnetic alloy
- antimonial lead
- antimonical lead
- antineutron
- antioxidant
- antioxidant additive
- antioxygen
- antiperoxide additive
- antipyretic
- antirad
- antireflective coating
- antirust grease
- antirust rust
- antiseptic ice
- antiseptic substance
- antishock
- antisludge additive
- antistalling agent
- antistat
- API scale
- apomagmatic
- apomagmatic deposit
- apparent density
- apparent dip
- apparent displacement
- apparent horizon
- apparent place
- apparent slip
- apparent velocity
- applicability
- applied
- aqua fortis
- aquiferous
- arborescent
- arch core
- argillaceous earth
- argillaceous liquid
- appraise
- Aptian stage
- aqueduct
- aqueous
- architectural concrete
- arenaceous texture