Etymology
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alight (v.)
"to descend (from horseback, etc.), dismount," Old English alihtan "alight," originally "to lighten, take off, take away," from a- "down, aside" (see a- (1)) + lihtan "get off, make light" (see light (v.)). The notion is of getting down off a horse or vehicle, thus lightening it. Of aircraft (originally balloons) from 1786. Related: Alighted; alighting.
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dispel (v.)
Origin and meaning of dispel

c. 1400, dispellen, "drive off or away," from Latin dispellere "drive apart," from dis- "away" (see dis-) + pellere "to drive, push" (from PIE root *pel- (5) "to thrust, strike, drive"). Since the meaning is "to drive away in different directions" it should not have as an object a single, indivisible thing (you can dispel suspicion, but not an accusation). Related: Dispelled; dispelling.

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way (adv.)
c. 1200, short for away (adv.). Many expressions involving this are modern and American English colloquial, such as way-out "far off;" way back "a long time ago" (1887); way off "quite wrong" (1892). Any or all of these might have led to the slang adverbial meaning "very, extremely," attested by 1984 (as in way cool).
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offset (n.)
1550s, "act of setting off" (on a journey, etc.), from off + set (adj.). Meaning "something 'set off' against something else, a counterbalance" is from 1769; the verb in this sense is from 1792. As a type of printing, in which the inked impression is first made on a rubber roller then transferred to paper, it is recorded from 1906.
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red herring (n.)

"smoked herring" early 15c. (they turn red when cured), as opposed to white herring "fresh herring." Supposedly used by fugitives to put bloodhounds off their scent (1680s), hence metaphoric sense (1864) of "something used to divert attention from the basic issue;" earlier it simply meant "a false lead":

Though I have not the honour of being one of those sagacious country gentlemen, who have so long vociferated for the American war, who have so long run on the red-herring scent of American taxation before they found out there was no game on foot; (etc.) [Parliamentary speech dated March 20, 1782, reprinted in "Beauties of the British Senate," London, 1786]
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rocker (n.)

1852, "a rocking chair," American English, agent noun from rock (v.1). Middle English had rokker, "nurse charged with rocking a cradle" (early 14c.). In sense of "one of the curved pieces of wood that makes a chair or cradle rock" it dates from 1787. Meaning "one who enjoys rock music" (opposed to mod (n.1)) is recorded from 1963, from rock (v.2).

Slang off (one's) rocker "crazy" is attested by 1897 according to OED; a widely reprinted 1903 newspaper column in U.S. identified it as British slang; the image is perhaps mechanical. To get (off) one's rocker seems to have been used earlier in U.S. baseball slang for "get busy, get active in a game" (1895) and does suggest the rocking-chair.

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of (prep.)

Old English of, unstressed form of æf (prep., adv.) "away, away from," from Proto-Germanic *af (source also of Old Norse af, Old Frisian af, of "of," Dutch af "off, down," German ab "off, from, down"), from PIE root *apo- "off, away."

The primary sense in Old English still was "away," but it shifted in Middle English with use of the word to translate Latin de, ex, and especially Old French de, which had come to be the substitute for the genitive case. "Of shares with another word of the same length, as, the evil glory of being accessory to more crimes against grammar than any other." [Fowler]

Also by 1837 of in print could be a non-standard or dialectal representation of have as pronounced in unstressed positions (could of, must of, etc.)

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explode (v.)

1530s (transitive), "to reject with scorn," from Latin explodere "drive out or off by clapping, hiss off, hoot off," originally theatrical, "to drive an actor off the stage by making noise," hence "drive out, reject, destroy the repute of" (a sense surviving in an exploded theory), from ex "out" (see ex-) + plaudere "to clap the hands, applaud," which is of uncertain origin. Athenian audiences were highly demonstrative. clapping and shouting approval, stamping, hissing, and hooting for disapproval. The Romans seem to have done likewise.

At the close of the performance of a comedy in the Roman theatre one of the actors dismissed the audience, with a request for their approbation, the expression being usually plaudite, vos plaudite, or vos valete et plaudite. [William Smith, "A First Latin Reading Book," 1890]

English used it to mean "drive out with violence and sudden noise" (1650s), later "cause to burst suddenly and noisily" (1794). Intransitive sense of "go off with a loud noise" is from 1790, American English; figurative sense of "to burst with destructive force" is by 1882; that of "burst into sudden activity" is from 1817; of population by 1959. Related: Exploded; exploding.

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bark (v.2)
"strip off the bark" (of a tree), 1540s, from bark (n.). Transferred sense "strip or rub off the skin" is from 1850. It also meant "kill a squirrel or other small animal by percussive force by shooting the bullet into the tree immediately below it," thus preserving the specimen intact (the technique is attested by 1828). Related: Barked; barking.
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rub (v.)

early 14c., rubben, transitive and intransitive, "apply friction on a surface; massage (the body or a part of it)," a word of uncertain origin, perhaps related to East Frisian rubben "to scratch, rub," and Low German rubbeling "rough, uneven," or similar words in Scandinavian (compare Danish rubbe "to rub, scrub," Norwegian rubba), all of uncertain origin. Related: Rubbed; rubbing.

To rub (someone) the wrong way is by 1853; probably the notion is of animals and their fur. To rub noses in greeting as a sign of friendship (attested from 1822) said to have been formerly common among Eskimos, Maoris, and some other Pacific Islanders. Rub out is from late 14c. as "scrape away," also figurative; the meaning "obliterate" is from 1560s; underworld slang sense of "kill" is recorded from 1848, American English. Rub off "remove by rubbing" is from 1590s; rub off on "have an influence on" is recorded by 1959.

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