witness mark n. generally, an intentional, accidental, or naturally occurring spot, line, groove, or other contrasting area that serves as an indicator of certain facts; in geography and surveying, a blaze, cut, hole, paint splash, or message written on a post, tree, rock or other guide to indicate a boundary, feature, or significant point on land, especially on a witness post; in construction and manufacturing, a line, groove, score, notch, cut, or written indicator made on the surface of material to impart information, such as where to cut or join; in forensic investigation, a surface groove, smear, stain, abrasion or other feature that can serve as evidence. (source: Double-Tongued Dictionary)
Further reading
Chase from Jacksonville, Florida, grew up in Sacramento, California, where kids played Rochambeau instead of rock, paper, scissors. Why the difference in names? Nobody knows. Folklorists call this a choosing game, and while the hand-game itself...
Amy from Charlotte, North Carolina, reports a dispute arose when visiting her brother’s family. Is a large container for storing sugar properly called a can or a canister? The answer involves prototype theory, which in cognitive linguistics and...
In process engineering, a witness mark can be the result of a particular process, the presence of which will prove that the process has occurred. E.g. A mark left on a test point from a test probe. However, in some circumstances, such marks are considered to be damaging and so efforts are made to avoid, prevent or eradicate such marks.