tip: English has three distinct words tip, two of them possibly related. Tip ‘extremity’ [15] was probably borrowed from Old Norse typpi. This was descended from prehistoric Germanic *tupp- ‘upper extremity’ (source also of English top and toupee). Tip ‘touch lightly’ [13] (as in ‘tip-and-run cricket’) may have been borrowed from Low German tippen, although it could be the same word as tip ‘extremity’ (from the notion of ‘just touching something with the tip of something else’).
It was used in 17th-century underworld argot for ‘give’ (as in ‘tip someone the wink’), and this evolved in the 18th century to ‘give a gratuity’. The antecedents of tip ‘overturn’ [14] (originally tipe) are not known, although the fact that it first appeared in northern dialects suggests that it may have been borrowed from a Scandinavian language. The derived tipsy [16] denotes etymologically ‘liable to fall over’. => top, toupee; tipsy[tip etymology, tip origin, 英语词源]