1) To strike or hit, a spelling of ‘knap’.
2) A knob or protuberance, often small and rounded, a boss. Used of kitchenware, particularly for the decorated ends of silver spoons.
1365 lego ... meliorem ciphum de murro vocatum knopmazer, York
1392 1 coclear argenti cum playn knope, York
1433 unam peciam argenti coopertam cum uno small knop ... unam peciam ... cum uno rownde knop ... unam peciam ... cum uno flatt knopp, Ripon
1558 I bequeathe to Henry Brame one siluer spone with a knope, Kirkstall
1657 one silver spoone with a gilded knope, Selby
1700 a silver spoon with a knop on the end, Selby. It could also refer to a decorative tuft or loop of material: 1612 2 sylken knoppes & other tryfling things, Brandsby and was occasionally employed adjectivally: 1401 j annulum auri knopped, York
1617 Twenty knopte silver spoones, sixtyne playne spounes, Ripley.