a leather strap used to sharpen razors
A strap; more specifically a piece of leather or a substitute (notably canvas), or strip of wood covered with a suitable material, for honing a razor, in this sense also called razor strop.
A poor-quality or unsaleable diamond.
To strap.
To mark a sequence of letters syntactically as having a special property, such as being a keyword, e.g. by enclosing in apostrophes as in 'foo' or writing in uppercase as in FOO.