"very roughly built house or cabin," 1878, American English and Canadian English, originally in reference to temporary dwellings made by homesteaders while securing a claim, a word of unknown origin. Perhaps it is from Mexican Spanish jacal (from Nahuatl (Aztecan) xacalli "wooden hut"). Or perhaps it is a back-formation from dialectal English shackly "shaky, rickety" (1843), a derivative of shack, a dialectal variant of shake (v.). Another theory derives shack from ramshackle.
Yet another derives it from the verb shack meaning "to hibernate," as a bear or other animal, which is also a variant of shake (v.) in the sense of "be shed or fall," used of grain fallen from the ear and available for food for hogs, etc. (1520s); hence "the act or right of sending pigs or poultry out to 'run shack' after a harvest." Also compare shake-down "impromptu bed made upon loose straw" (1730).
The slang meaning "house" is attested by 1910. In early radio enthusiast slang, it was the word for a room or office set aside for wireless use, 1919, perhaps from earlier U.S. Navy use (1917).
The perhaps-related verb in the "hibernate" sense by 1891 in the U.S. West was used in reference to men who "hole up" for the winter; it is attested from 1927 as "to put up for the night;" the phrase shack up "cohabit" is recorded by 1935 (Zora Neale Hurston).
Old English up, uppe, from Proto-Germanic *upp- "up" (source also of Old Frisian, Old Saxon up "up, upward," Old Norse upp; Danish, Dutch op; Old High German uf, German auf "up"; Gothic iup "up, upward," uf "on, upon, under;" Old High German oba, German ob "over, above, on, upon"), from PIE root *upo "under," also "up from under," hence also "over."
As a preposition, "to a higher place" from c. 1500; also "along, through" (1510s), "toward" (1590s). Often used elliptically for go up, come up, rise up, etc. Up the river "in jail" first recorded 1891, originally in reference to Sing Sing, which is up the Hudson from New York City. To drive someone up the wall (1951) is from the notion of the behavior of lunatics or caged animals. Insulting retort up yours (scil. ass) is attested by late 19c.
1550s, "to drive and catch (swans)," from up (adv.). Intransitive meaning "get up, rise to one's feet" (as in up and leave) is recorded from 1640s. Sense of "to move upward" is recorded from 1737. Meaning "increase" (as in up the price of oil) is attested from 1915. Compare Old English verb uppian "to rise up, swell." Related: Upped; upping. Upping block, used for mounting or dismounting horses, carriages, etc., is attested from 1796 (earlier was horsing-block, 1660s).
