Origin and history of high-wire

Old English heh (Anglian), heah (West Saxon) "of great height, tall, conspicuously elevated; lofty, exalted, high-class," from Proto-Germanic *hauha- (source also of Old Saxon hoh, Old Norse har, Danish høi, Swedish hög, Old Frisian hach, Dutch hoog, Old High German hoh, German hoch, Gothic hauhs "high;" also German Hügel "hill," Old Norse haugr "mound"). The group is of uncertain origin; perhaps related to Lithuanian kaukara "hill," from PIE *kouko-. Spelling with -gh represents a final guttural sound in the original word, lost since 14c.

Of sound pitch, late 14c. Of roads, "most frequented or important," c. 1200 (high road in the figurative sense is from 1793). Meaning "euphoric or exhilarated from alcohol" is first attested 1620s, of drugs, 1932. Sense of "proud, haughty, arrogant, supercilious" (c. 1200) is reflected in high-handed and high horse. Of an evil or a punishment, "grave, serious, severe" (as in high treason), c. 1200 (Old English had heahsynn "deadly sin, crime").

High school "school for advanced studies" attested from late 15c. in Scotland; by 1824 in U.S. High time "fully time, the fullness of time," is from late 14c.; also "last possible moment" (early 15c.). High noon (when the sun is at the meridian) is from early 14c.; the sense is "full, total, complete." High finance (1884) is that concerned with large sums. High tea (1831) is one at which hot meats are served. High-water mark is what is left by a flood or highest tide (1550s); figurative use by 1814.

High and mighty is c. 1200 (heh i mahhte) "exalted and powerful," formerly a compliment to princes, etc. High and dry of beached things (especially ships) is from 1783.

Middle English wir, from Old English wir "elastic metal drawn out into a strand or thread," from Proto-Germanic *wira- (source also of Old Norse viravirka "filigree work," Swedish vira "to twist," Old High German wiara "fine gold work"), from PIE root *wei- "to turn, twist, plait." In early use of fine gold filigree worn ornamentally in the hair, etc.

In reference to the metallic strings of a musical instrument from late 14c. A wire as marking the finish line of a racecourse is attested from 1883; hence the figurative down to the wire. Wire-rim, of eye-glasses, is by 1968 (mentioned with mini-skirts and sideburns as characteristic of high school students).

The sense of "line of wire as an electrical conduit" is by 1747. Specifically as "telegraph wire" by 1846, thus "telegraph system" generally (by 1859; also see wire (v.)). Hence also the journalistic wire service (by 1894), transmitting news to client papers by wire, and the wire generically in newsrooms for "news of the nation and world."