Roofing Terms & Definitions. Asphalt: A bituminous waterproofing agent applied to roofing materials during manufacturing. Back Surfacing: Fine mineral matter applied to the backside of shingles to keep them from. sticking. Blisters: Bubbles that may appear on the surface of asphalt roofing after installation.
Symbol(noun) an abbreviation standing for the name of an element and consisting of the initial letter of the Latin or New Latin name, or sometimes of the initial letter with a following one; as, C for carbon, Na for sodium (Natrium), Fe for iron (Ferrum), Sn for tin (Stannum), Sb for antimony (Stibium), etc.
Symbol (chemistry) In relation to the chemical elements, a symbol is a code for a chemical element. Many functional groups has their own chemical symbol, e.g. Ph for the phenyl group, and Me for the methyl group.