early 14c. as a verbal phrase, "lift and take with the fingers," from pick (v.) + up (adv.). From 1510s as "take or get casually, obtain or procure as opportunity offers." Meaning "take (a person found or overtaken) into a vehicle or vessel," is from 1690s, also, of persons, "make acquaintance or take along" (especially for sexual purposes). Intransitive meaning "improve gradually, reacquire vigor or strength" is by 1741. Sense of "tidy up" is from 1861; that of "arrest" is from 1871; meaning "gain speed" is from 1922; meaning "to pay" (a check, tab, etc.) is from 1945. Pick-me-up "stimulating alcoholic drink" is attested from 1867.
"multi-vehicle crash," 1929, from verbal phrase pile up "to heap up" (c. 1400), which is attested from 1849 as "to accumulate," 1899 as "to wreck in a heap" (see pile (v.)).
command to a horse to go, 1909, probably an extended form of earlier giddap (1867), itself probably from get up. Compare gee.
The terms used to start horses in harness and to urge them to a better appreciation of the value of time comprise vulgar corruptions of ordinary speech and peculiar inarticulate sounds. Throughout England and the United States drivers start their horses by picking up the reins, drawing them gently against the animals' mouths, and exclaiming go 'long and get up; the latter appears in the forms get ap (a as in hat), giddap, and gee-hup or gee-up. [H. Carrington Bolton, "Talking to Domestic Animals," in The American Anthropologist, March 1897]
1837, "act of bringing a horse or vehicle to a sudden stop," from the verbal phrase; see pull (v.) + up (adv.). To pull up is attested by early 14c. as "lift (someone or something)," late 14c. as "uproot." By 1887 as "a place for pulling up a vehicle." The noun, as a type of horizontal bar physical exercise involving pulling up the body by means of the arms, is attested by 1891.
The sense of "check a course of action" is from 1808, figurative of the lifting of the reins in horse-riding; pull (v.) in the sense of "check or hold back one's horse to keep it from winning" is by 1800.
"furious exchange of gunfire," by 1922, from the verbal phrase shoot up "assail by shooting, rampage with guns" (1890); see shoot (v.) + up (adv.). The phrase is attested in late Old English, but in a sense of "well up, overflow." Shoot-'em-up (adj.) in reference to violent entertainment (Western movies, etc.) is from 1942.