firecracker n.

mid-15c., "hard wafer," literally "that which cracks or breaks," agent noun from crack (v.). The specific application to a thin, hard or crisp biscuit is by 1739, mostly in American English; the meaning "instrument for crushing or cracking" is from 1630s (compare nut-cracker).

Coal-cracker is from 1853 of persons, 1857 of machinery that breaks up mined coal. The cracker-barrel (1861) full of soda-crackers for sale was such a common feature in the popular perception of country stores that the phrase came to be used by 1905 as an adjective, "emblematic of down-home ways and views."

Old English fyr "fire, a fire," from Proto-Germanic *fūr- (source also of Old Saxon fiur, Old Frisian fiur, Old Norse fürr, Middle Dutch and Dutch vuur, Old High German fiur, German Feuer "fire"), from PIE *perjos, from root *paewr- "fire." Current spelling is attested as early as 1200, but did not fully displace Middle English fier (preserved in fiery) until c. 1600.

PIE apparently had two roots for fire: *paewr- and *egni- (source of Latin ignis). The former was "inanimate," referring to fire as a substance, and the latter was "animate," referring to it as a living force (compare water (n.1)).

Brend child fuir fordredeþ ["The Proverbs of Hendyng," c. 1250]

English fire was applied to "ardent, burning" passions or feelings from mid-14c. Meaning "discharge of firearms, action of guns, etc." is from 1580s. To be on fire is from c. 1500 (in fire attested from c. 1400, as is on a flame "on fire"). To play with fire in the figurative sense "risk disaster, meddle carelessly or ignorantly with a dangerous matter" is by 1861, from the common warning to children. Phrase where's the fire?, said to one in an obvious hurry, is by 1917, American English.

Fire-bell is from 1620s; fire-alarm as a self-acting, mechanical device is from 1808 as a theoretical creation; practical versions began to appear in the early 1830s. Fire-escape (n.) is from 1788 (the original so-called was a sort of rope-ladder disguised as a small settee); fire-extinguisher is from 1826. A fire-bucket (1580s) carries water to a fire. Fire-house is from 1899; fire-hall from 1867, fire-station from 1828. Fire company "men for managing a fire-engine" is from 1744, American English. Fire brigade "firefighters organized in a body in a particular place" is from 1838. Fire department, usually a branch of local government, is from 1805. Fire-chief is from 1877; fire-ranger from 1887.

Symbolic fire and the sword is by c. 1600 (translating Latin flamma ferroque absumi); earlier yron and fyre (1560s), with suerd & flawme (mid-15c.), mid fure & mid here ("with fire and armed force"), c. 1200. Fire-breathing is from 1590s. To set the river on fire, "accomplish something surprising or remarkable" (usually with a negative and said of one considered foolish or incompetent) is by 1830, often with the name of a river, varying according to locality, but the original is set the Thames on fire (1796). The hypothetical feat was mentioned as the type of something impossibly difficult by 1720; it circulated as a theoretical possibility under some current models of chemistry c. 1792-95, which may have contributed to the rise of the expression.

[A]mong other fanciful modes of demonstrating the practicability of conducting the gas wherever it might be required, he anchored a small boat in the stream about 50 yards from the shore, to which he conveyed a pipe, having the end turned up so as to rise above the water, and forcing the gas through the pipe, lighted it just above the surface, observing to his friends "that he had now set the river on fire." ["On the Origins and Progress of Gas-lighting," in "Repertory of Patent Inventions," vol. III, London, 1827]

Old English cracian "make a sharp noise, give forth a loud, abrupt sound," from Proto-Germanic *krakojan (source also of Middle Dutch craken, Dutch kraken, German krachen); the whole group is probably ultimately imitative. Related: Cracked; cracking.

From c. 1300 as "to burst, split open" (intransitive), also transitive, "to cause to break into chinks." From 1785 as "break or crush into small pieces." Of the voice, "change tone suddenly," as that of a youth passing into manhood, c. 1600. Meaning "to open and drink" (a bottle) is from 16c.

From early 14c. as "to utter, say, speak, talk freely," especially "speak loudly or boastingly" (late 14c.). To crack a smile is from 1835, American English; to crack a joke is by 1732, probably from the "speak, say" sense. To crack the whip in the figurative sense is from 1886. Get cracking "go to work, start doing what is to be done" is by 1937.

What is a crack in English? A chat! The synonym is as perfect as possible; yet the words are subtly distinguished by a whole hemisphere of feeling. A chat, by comparison "wi' a crack," is a poor, frivolous, shallow, altogether heartless business. A crack is, indeed, only adequately to be defined as a chat with a good, kindly, human heart in it .... [P.P. Alexander, notes to "Last Leaves," Edinburgh, 1869]