1809. G. Andrews, Dict. of the Slang and Cant Languages, s.v. Flooring, subs. (pugilists’).—Knocking down. Hence, to vanquish in all senses. 1819. Moore, Tom Crib’s Memorial, p. xii. Cross-buttocking ... being as indispensable an ingredient, as nobbing, flooring, etc. Floor-walker, subs. (American).—A shop-walker. Flop, subs. and verb. (American university).—1. A bite (q.v.); a successful dodge. 1856. Hall, College Words and Customs. Any ‘cute’ performance by which a man is sold is a good flop, and by a phrase borrowed from the base-ball ground is ‘rightly played.’ The discomfited individual declares that they ‘are all on a side,’ and gives up, or ‘rolls over,’ by giving his opponent ‘gowdy.’ A man writes cards during examinations to ‘feeze the profs’; said cards are ‘gumming cards,’ and he flops the examination if he gets a good mark by the means. One usually flops his marks by feigning sickness. 2. (common)—A sudden fall or ‘flop’ down. 3. (common).—A collapse or breakdown. 4. (For flap or flip, old).—A light blow. 1662. Rump Songs, ii., 3. The good the Rump will do, when they prevail, Is to give us a flop with a fox’s tail, Which nobody can deny. Verb. (colloquial).—1. To fall, or flap down suddenly. A variant of ‘flap.’ Fr., prendre un billet de parterre. 1742. Fielding, Joseph Andrews, bk. iv. ch. v. She had flopped her hat over her eyes. 1859. Dickens, Tale of Two Cities, bk. ii. ch. i. If you must go flopping yourself down. 1870. Public Opinion, 12 Feb. But even if they were more numerous and greater than they are, we should hold aloof from the crowd that flops in his presence with love and awe, as the dismal wife of Jerry Cruncher flopped in pious misery. 1883. The Theatre, Feb., p. 93. She is able to call in tumbling to the aid of tragedy, and bring the plastic arts to the portrayal of the passions; to flop through four such acts as these night after night, and finish with a death-scene warranted correct, to the very last kick and quiver. 1891. Hume Nisbet, Bail Up! p. 118. He cursed under his breath each time he rose to follow, and smothered a yell of pain and horror each time he flopped down. 2. (pugilists’).—To knock down; to Floor (q.v.). 1888. Sporting Life, 15 Dec. ’E carnt flop a bloke. Adv. (colloquial).—An onomatopœia expressive of the noise of a sudden and sounding fall. Often used expletively, as slap (q.v.) is, and the American right (q.v.) 1726. Vanbrugh, Journey to London, Act I., Sc. 2. That down came I flop o’ my feace all along in the channel. 1860. Punch, v. 38, p. 255. ’Twixt two stools, flop, he let me drop, The fall it was my murther. 1881. Jas. Payn, Grape from a Thorn, ch. vi. ‘She’ll roll down, papa, and come flop.’