1823, "act of flopping; any action that produces the sound 'flop;' the sound itself," from flop (v.). Figurative sense of "a failure; that which is a failure" is by 1893, from the notion of a sudden break-down or collapse. Extended form flopperoo is attested by 1936. The Fosbury flop high-jumping technique (1968) is so called in reference to U.S. athlete Dick Fosbury (b. 1947), who used it to win the 1968 Olympic gold medal.
c. 1600, "to flap," probably a variant of flap with a duller, heavier sound. Sense of "fall or drop heavily" is 1836; that of "collapse, fail" is 1919; though the figurative noun sense of "a failure" is recorded from 1893. Related: Flopped; flopping.
"cheap hotel," hobo slang, 1904, probably related to slang flop (v.) "lie down for sleep" (1907); see flop (v.) + house (n.). The explanation below is not found in other early references.
In one of [Cincinnati's] slum districts stands the Silver Moon, a "flop house" (i.e., a house where the occupants are "flopped" out of their hanging bunks by letting down the ropes) .... [McClure's magazine, November 1904]
also flip flop, "plastic thong beach sandal," by 1970, imitative of the sound of walking in them. Flip-flap had been used in various senses, mostly echoic or imitative of a kind of loose flapping movement, since 1520s:
Flip-flaps, a peculiar rollicking dance indulged in by costermongers, better described as the double shuffle; originally a kind of somersault. [Hotten's Slang Dictionary, 1864]
Flip-flop in the general sense of "complete reversal of direction" dates from 1900; it began to be used in electronics in the 1930s in reference to switching circuits that alternate between two states. As a verb by 1897. Flop (n.) in the sense "a turn-round, especially in politics" is from 1880.
"botch, bungle," 1924, American English, of uncertain origin, perhaps suggested by fluff, flop, etc. Related: Flubbed; flubbing. As a noun, by 1952.
"struggle awkwardly and impotently," especially when hampered somehow, 1590s, of uncertain origin, perhaps from an alteration of founder (n.), influenced by Dutch flodderen "to flop about," or native verbs in fl- expressing clumsy motion. Figurative use is from 1680s. Related: Floundered; floundering. As a noun, "act of struggling," by 1867.
1540s, "to dash, plunge, flop," perhaps from Scandinavian (compare dialectal Swedish flunsa "to plunge," Norwegian flunsa "to hurry, work hurriedly," but first record of these is 200 years later than the English word), said to be of imitative origin. Spelling likely influenced by bounce. Notions of "anger, impatience" began to adhere to the word 18c. Related: Flounced; flouncing. As a noun from 1580s in reference to a sudden fling or turn of the body; by mid-18c. especially as expressing impatience or disdain.
1855, theater slang for "a failure in performance;" by 1862 it had acquired the general sense of "any ignominious failure or dismal flop," on or off the stage. It comes via the French phrase faire fiasco "turn out a failure" (19c.), from Italian far fiasco "suffer a complete breakdown in performance," literally "make a bottle," from fiasco "bottle," from Late Latin flasco "bottle" (see flask).
The literal sense of the image (if it is one) is obscure today, but "the usual range of fanciful theories has been advanced" [Ayto]. Century Dictionary says "perhaps in allusion to the bursting of a bottle," Weekley pronounces it impenetrable and compares French ramasser un pelle "to come a cropper (in bicycling), literally to pick up a shovel." OED keeps its distance and lets nameless "Italian etymologists" make nebulous reference to "alleged incidents in Italian theatrical history." Klein suggests Venetian glass-crafters tossing aside imperfect pieces to be made later into common flasks. But according to an Italian dictionary, fare il fiasco used to mean "to play a game so that the one that loses will pay the fiasco," in other words, he will buy the next bottle (of wine). If the dates are not objectionable, that plausibly connects the literal sense of the word with the notion of "a costly mistake."