The Medieval Latin word could as well be influenced by the rough agreement of the Arabic term with classical Latin semita "sidetrack, side path" (notion of "thing going off to the side"), from se- "apart" + *mi-ta-, a suffixed form of PIE root *mei- (1) "to change, go, move." Figurative sense of "highest point or state" is from c. 1600.
late 14c., in astronomy, "imaginary point of the celestial sphere vertically opposite to the zenith of the sun; the inferior pole of the horizon," from Medieval Latin nadir, from Arabic nazir "opposite to," in nazir as-samt, literally "opposite direction," from nazir "opposite" + as-samt "road, path" (see zenith). Transferred sense of "lowest point" of anything is recorded by 1793.
It forms all or part of: amiss; amoeba; azimuth; common; commune; communicate; communication; communism; commute; congee; demean; emigrate; emigration; excommunicate; excommunication; immune; immutable; incommunicado; mad; mean (adj.1) "low-quality;" mew (n.2) "cage;" mews; migrate; migration; mis- (1) "bad, wrong;" mistake; Mithras; molt; Mstislav; municipal; munificent; mutable; mutant; mutate; mutation; mutatis mutandis; mutual; permeable; permeate; permutation; permute; remunerate; remuneration; transmutation; transmute; zenith.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit methati "changes, alternates, joins, meets;" Avestan mitho "perverted, false;" Hittite mutai- "be changed into;" Latin mutare "to change," meare "to go, pass," migrare "to move from one place to another," mutuus "done in exchange;" Old Church Slavonic mite "alternately;" Czech mijim "to go by, pass by," Polish mijać "avoid;" Gothic maidjan "to change."
Old English norð- (in compounds) "northern, lying to the north" (adj.); norð (adv.) "northwards, to the north, in the north;" from Proto-Germanic *nurtha- (source also of Old Norse norðr, Old Saxon north, Old Frisian north, Middle Dutch nort, Dutch noord, German nord), which is probably an IE word, but of uncertain origin.
It might be ultimately from PIE *ner- (1) "left," also "below" (source also of Sanskrit narakah "hell," Greek neretos "deeper, lower down," enerthen "from beneath," Oscan-Umbrian nertrak "left"), as north is to the left when one faces the rising sun. The same notion apparently underlies Old Irish tuath "left; northern;" Arabic shamal "left hand; north." Compare Benjamin. Or perhaps the notion is that the sun is at its "lowest" point when in the north.
The usual word for "north" in the Romance languages ultimately is from English: Old French north (Modern French nord), borrowed from Old English norð; and Italian nord, Spanish norte, borrowed from French.
As a noun, "the northern cardinal point or direction," late 12c., from the adjective. From c. 1200 as "the north part of Britain, the region beyond the Humber." Generally, then "a region lying north of some other region." In U.S. history, "the states and territories north of Maryland and the Ohio River" (by 1796).
The geographical North Pole is attested from mid-15c. (earlier the Arctic pole, late 14c.; north pole in astronomy for "the fixed zenith of the celestial sphere" is from late 14c.). North American (n.) was used in 1766 by Franklin; as an adjective from 1770.
Ask where's the North? At York 'tis on the Tweed;
In Scotland at the Orcades; and there
At Greenland, Zembla, or the Lord knows where.
[Pope, "Essay on Man"]