What the word means now
Call a coincidence strange and you usually mean that it is odd, unexpected, or hard to explain. The same adjective can still mark something merely unfamiliar: a strange city, a strange accent, a face you have not seen before. Those two layers sit side by side in modern English. One names deviation from a pattern. The other names distance from what a speaker already knows. Reserved or awkward manner, inexperience with a task, and a technical flavour in particle physics remain on the books, but they are narrower uses. The origin of the word strange is less a tale of weirdness than of standing outside.
A French loan in Middle English
English did not inherit this adjective from Old English. It came in as a borrowing from French during the Middle English period. The source is Old French estrange, with Anglo-French spellings estraunge, strange, and straunge. Those forms yielded Middle English straunge and close variants, including strounge in early use. The Oxford English Dictionary’s first evidence is around 1290, in the legend of St. Brendan. Other chronological notes are slightly looser and place first English use in the late thirteenth century, about 1250 to 1300. The difference is a matter of how tightly a first date is pinned, not of a rival etymology.
The Norman surname Lestrange is already attested in the late twelfth century. That does not prove the English adjective was current then, but it does show the French form circulating among people in England before the word is securely recorded in English narrative.
Native vocabulary that had covered nearby ground gave way. Old English fremede, seldcūþ, and uncūþ had marked the foreign, the seldom known, and the unknown. Uncouth survived, but with a narrowed social colour. The French loan took the central work of naming what came from elsewhere.
Built on Latin extra
Old French estrange is the regular descendant of Latin extraneus: foreign, external, from without. That adjective is formed on extra, outside, from exter, outward. The suffix is the ordinary Latin -aneus, so the shape is transparent: belonging to what lies beyond a boundary. English later took the same Latin word a second time, in the 1630s, as the learned adjective extraneous. The pair are doublets. One arrived through medieval French speech and spelling; the other arrived through books. They still share a family likeness. Extraneous is what does not belong inside a thing. Strange, at the start, was what did not belong in a place.
Romance cognates keep both the foreign sense and the later odd sense. Modern French étrange, Italian strano, Spanish extraño, and Portuguese estranho continue the same line. French lost the s and marks the lost consonant with a circumflex. English dropped the opening vowel of estraunge and kept the cluster str-. Related English words include extra, estrange, and stranger. None of this depends on a folk story about the spelling. The path from extra to extraneus to estrange is a regular one.
From foreigner to oddity
In early Middle English the dominant sense was spatial and social. A person, a tongue, a rite, or a country could be strange because it came from elsewhere: another land, another town, another guild, household, or religious group. The word could mark someone who lacked citizenship, kinship, or membership. It did not yet have to mean that the person’s behaviour was peculiar. The Middle English record uses it of lands, foods, clothes, and languages that were simply not local, and sometimes of things that were elaborate or outlandish rather than native and plain.
The sense of surprising or queer is already implied around 1300, so the move from unknown to unaccountable was quick. What you have not met is easy to hear as what does not fit. By the mid-fourteenth century the adjective could also mean aloof, reserved, distant in manner, like someone who will not close the gap. In the mid-fifteenth century English speakers could make strange: act surprised or shocked. Coverdale’s 1535 Bible used strange woman for a woman not one’s own, in the sense of an adulteress or harlot, following Hebrew terms that meant belonging to another. By the 1660s the word could stand alone as an interjection of wonder.
The physics sense is a twentieth-century overlay, not a continuation of the medieval social meaning. In the 1950s Murray Gell-Mann, Kazuhiko Nishijima, and others named a new conserved quantity strangeness because certain particles were produced readily yet decayed far more slowly than their masses led physicists to expect. The adjective in particle physics is recorded from the mid-1950s; the strange quark proposed in 1964 inherited the label. Here the everyday idea of unexpected behaviour was applied, quite openly, to subatomic facts.
The doublet that still shows the root
The cleanest trace of the history is the pair strange and extraneous. One was worn down in French mouths and English spelling. The other was lifted from Latin in the seventeenth century. Both still mean, in different registers, what lies outside. The oddness we hear first today is a later colour on a word that first said: not from here.