Etymology
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through (prep., adv.)

late 14c., metathesis of Old English þurh, from Proto-Germanic *thurx (source also of Old Saxon thuru, Old Frisian thruch, Middle Dutch dore, Dutch door, Old High German thuruh, German durch, Gothic þairh "through"), from PIE root *tere- (2) "to cross over, pass through, overcome." Not clearly differentiated from thorough until early Modern English. Spelling thro was common 15c.-18c. Reformed spelling thru (1839) is mainly American English.

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follow-through (n.)
1896, of golf swings, from verbal phrase follow through; see follow (v.) + through (adv.). Figurative use from 1926.
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drive-through (adj.)

"that may be used or experienced while driving a car," 1949 (in an advertisement for the Beer Vault Drive-Thru in Ann Arbor, Michigan), from the verbal phrase; see drive (v.) + through (adv.).

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walk-through (n.)
also walkthrough, 1944, "an easy part" (in a theatrical production), from walk (v.) + through. Meaning "dry run, full rehearsal" is from 1959, from the notion of "walking (someone) through" something.
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run-through (n.)

"a rehearsal," especially a hasty one, 1923, from the verbal phrase; see run (v.) + through (adv.). The verbal phrase is attested by mid-15c. as "examine, inspect;" by 1670s as "read over rapidly." Its sense of "to pierce or stab through the body" is from late 15c.

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go through (v.)
"to execute, carry to completion" (a plan, etc., often with with), 1560s; see go (v.) + through (adv.). Meaning "to examine" is 1660s; "to endure, suffer, undergo" is by 1712; "to wear out" (of clothes, etc.) by 1959.
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see-through (adj.)

1950, from the verbal phrase, "see things on the other side of" (c. 1400); see see (v.) + through (adv.). The verbal phrase see through often is figurative, "perceive the real character of, detect imposture." To see (something) through "continue with until the end" is by 1828 (to see (something) out in the same sense is from 1782).

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throughput (n.)
"energy, activity," 1808, Scottish slang; from through + put. Industrial sense is from 1915.
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throughway (n.)
"expressway, large toll road," 1934, American English, from through + way (n.).
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