also sunup, "sunrise," 1712, from sun (n.) + up (adv.). In local use in U.S., and, according to OED, also in Caribbean English and formerly in South Africa.

also startup, 1550s, "upstart," from verbal phrase (attested from c. 1200 in sense "rise up;" 1590s as "come suddenly into being"); see start (v.) + up (adv.). Meaning "action of starting up" is from 1845. See start (v.) + up (adv.).

1670s, of clothing, "adapted for being pinned up," from the verbal phrase (attested from mid-15c. in the sense "affix in a prominent place"), from pin (v.) + up (adv.). From 1940, in reference to pictures of "winsome young ladies in daring undress" ("Life," May 6, 1940) such as soldiers pinned up on their dugout walls, etc. The thing itself is older than the name. The noun in this sense is recorded from 1943.

"state of confusion," 1841, from the colloquial verbal phrase mix up "to confuse, entangle mentally" (1806), from mix (v.) + up (adv.). Of fighters, to mix it up "exchange blows" is by 1898.

also chinup, type of exercise, 1940, from chin (v.) + up (adv.). Earlier it was called chinning the bar and under names such as this is described by 1883.

"even matter," 1809, from earlier sense of "a flipping of a coin to arrive at a decision" (c. 1700), from verbal phrase, from toss (v.) + up (adv.).

"mature," late 14c., past-participle adjective from grow up. The noun meaning "adult person" is from 1813, short for grown-up person, etc.

1961 in reference to a data transmission link via public telephone network, from the verbal phrase; see dial (v.) + up (adv.).

"diagnostic examination of a patient," 1961, from the verbal phrase; see work (v.) + up (adv.).

"a working to overtake a leading rival," by 1971, probably a figurative use from U.S. football in reference to being behind in the score. The verbal phrase catch up was used from early 14c. in the sense of "raise aloft," it is attested from c. 1400 as "to take up suddenly," and by 1846 in the sense of "get to the same point, overtake;" see catch (v.) + up (adv.).