rub [ME] The origin of this word is unknown, although there are parallels in other Germanic languages. To rub someone up the wrong way is from the idea of stroking a cat against the lie of its fur. Someone pointing out a particular difficulty may say there’s the rub. The expression comes from Shakespeare’s Hamlet, when Hamlet says: ‘To sleep: perchance to dream: ay, there’s the rub.’ In the game of bowls a rub is an impediment that prevents a bowl running smoothly. Rubber [LME] had an original sense ‘an implement (such as a hard brush) used for rubbing and cleaning’. Because an early use of the elastic substance once known as caoutchouc was to rub out pencil marks, rubber acquired the sense ‘eraser’ in the late 18th century. The meaning was subsequently generalized in the mid 19th century to refer to the substance in any form or use, at first often differentiated as India rubber [L18th].