||AAMA – American Architectural Manufacturers Association
||Abrasion Resistance – the ability to resist being worn away by contact with another moving, abrasive surface, such as foot traffic, mechanical equipment, wind-blown particles, etc.
||Absorption – the ability of a material to accept within its body, quantities of gases or liquid, such as moisture.
||Accelerated Weathering – the exposure of a specimen to a specified test environment for a specified time with the intent of producing in a shorter time period, effects similar to actual weathering.
||ACI – American Concrete Institute
||Acid etch – in waterproofing, the use of a strong acid to remove the surface of concrete to expose the aggregate.
||ACIL – American Council of Independent Laboratories
||Acrylic coating – a liquid coating system based on an acrylic resin. Generally, a latex-based coating system that cures by air drying.
||Acrylic resin – polymers of acrylic or methacrylic monomers. Often used as a latex base for coating systems.
||Active metal (anodic) – a metal or material that readily gives up electrons to a cathodic (noble) material. (See anodic). An active metal will corrode in the presence of moisture when in contact with a cathodic metal.