sea-monster said to appear from time to time off the coast of Norway, 1755, from Norwegian dialectal krake (the -n is the definite article as a suffix), apparently a special use of krake "pole, stake, post," also "crooked tree, stunted animal or person."

The popular notion of the kraken dates back at least to the time of Pontoppidan (1698-1764), who wrote a description of it. One of the giant squids, as a cephalopod of the genus Architeuthis, might furnish a reasonable basis for the myth. [Century Dictionary]

Middle English craken, from 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 "burst, split open" (intransitive), also transitive, "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. The meaning "open and drink" (a bottle) is from 16c.

From early 14c. as "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. To 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]