formstoneEtymologyA genericization from a trade name of the 1940s, FormStone, itself a proprialization from what had previously been a lexical gap compound, form + stone.formstone means A plasterlike artificial stone compound made to resemble stone (rock); the stonelike (rocklike) veneer thus produced. Lexicurio rates it Sui generis — a strength score of 89 out of 100.nounA plasterlike artificial stone compound made to resemble stone (rock); the stonelike (rocklike) veneer thus produced.“Near-synonym: permastone (broadly synonymous)”