"interior regions," 1680s, from up- + country (n.). As an adjective from 1810; as an adverb from 1864.

1882, from the verbal phrase; see write (v.) + up (adv.).

"a joining together or coupling," 1945, from the verbal phrase; see link (v.) + up (adv.).

1830 as the name of a children's game (OED describes it as "all-fours" when played for seven "chalks"); with capital initials, as the proprietary name of a brand of carbonated drink, it is attested from 1928.

verbal phrase, by 1826 as "to disgrace through exposure;" see show (v.) + up (adv.). The meaning "to put in an appearance, be (merely) present" is by 1888. The noun sense of "an exposure of something concealed" is by 1830, colloquial.

"adjustments made to an automobile to improve its working," 1911, from verbal phrase tune up "bring to a state of effectiveness," 1718, in reference to musical instruments, from tune (v.) + up (adv.). Attested from 1901 in reference to engines. Meaning "event that serves as practice for a later one" is from 1934, U.S. sports jargon.

"add strength," 1941, from college slang, from beef (n.) in slang sense of "muscle-power" (1851).

also cleanup, 1856, "act of cleaning up,  a general cleaning," from clean + up. Meaning "a profit" is recorded from 1878. Verbal phrase clean up "make a large profit" is from 1929. The adjective, in the baseball sense, is recorded by 1910 in reference to the hitter who bats fourth in the lineup: His job is to drive in runs by scoring the players who hit before him and thus "clean up" the bases.

"clever, alert," 1926, from warning cry "heads up!" (i.e. "look up!"). As a noun, "a notification, a warning," by 1988.

also pushup, type of physical exercise (originally done on parallel bars), 1893, from the verbal phrase (by 1660s); see push (v.) + up (adv.). As an adjective, "that pushes up or may be pushed up," from 1892; of bras from 1957. Related: Push-ups