Etymology: see bounce v. (The first three senses appear nearly simultaneously, and their order here is purely provisional.)

Etymology: Origin uncertain. Perhaps < bounce v., although if so the semantic motivation is unclear.

Etymology: The origin of main sense, bounce n.¹, bounce int. and adv. is obscure, and their mutual relations complicated. Middle English bunsen agrees in form and meaning with modern Dutch bons a thump, bonzen (Low German bunsen , High German dialect bumbsen ) to beat, thump, thwack; but there is no early record of these words, and perhaps they may be related to the English word merely as parallel onomatopoeic formations. Early in 16th cent. we find the interjectional use of bounce (= Low German and High German dialect bums! ) to imitate the report of a gun or other loud sudden noise, and (a little later) to express sudden or violent movement. About the same time the verb (previously seldom occurring) became common in its original sense ‘to beat’, but with the notion of noise or vehemence more conspicuous—‘to knock, bang’; it also acquired the senses ‘to make a banging or explosive noise’, and ‘to make a sudden or violent movement of a bounding nature’. The noun is also found in all these senses early in the 16th cent. Whether these were natural developments of the original sense, as expressing phenomena which often accompany a knock or thump, or at least are present in the bang of cannon (which had come into use just before these extensions of bounce ), or whether there has been influence of any other words is not clear. The development of sense however is to a great extent parallel to that of bang v.¹, which has dialectally even the sense of ‘bounce into a room’, etc.

Etymology: The stem of the verb or noun interjectionally: compare the corresponding use of German bums, bumps, as in bums geht die Thür (Grimm).