alum - arc
- American Bureau of Metal Statistics
- American Die-Casting Institute
- American Foundrymen's Association
- American Institute of Mining, Metallurgical and Petroleum Engineers
- American malleable (cast) iron
- American Refractories Institute
- American Society for Metals
- American Zinc Institute
- americium
- ammonia aqua
- ammonia gas
- ammonia leaching
- ammonia-base atmosphere
- ammoniacal liquor
- amorphous
- amorphous condition
- amorphous dust
- amorphous powder
- amorphous solid
- amorphous sulphur
- amount of exposure
- amount of order
- amount of reduction
- amount of shrinkage
- amount of slip
- amount of temperature interval
- amount of wear
- ampere-turn per meter
- amperometric titrimeter
- amperometrical method
- amphion
- amphoteric compound
- amphoteric conductor
- amphoteric metal
- ampl
- ample supply of air
- amplitude dependence of internal friction
- amplitude frequency response
- amplitude-dependent internal friction
- AMS