Английский Этимологический словарь - stop (v.)

- O.E. -stoppian (in forstoppian "to stop up, stifle"), a W.Gmc. borrowing from V.L. *stuppare "to stop or stuff with tow or oakum." Plugs made of tow were used from ancient times in Rhine valley. Sense of "bring or come to a halt" (1440) is from notion of preventing a flow by blocking a hole, and is only in Eng. Stopgap is from 1684. Stop-watch is from 1737. Phrase stop on a dime first attested 1964.