A word for difference itself
English speakers put a heavy load on change. The verb can mean to make something different, to put one thing in another’s place, or simply to become other than it was. The noun can name the act, the result, a substitute, leftover coins after a purchase, or even a shift of clothes. Those uses look scattered until they are lined up historically. They grow from a single older idea: giving one thing and taking another.
That commercial grain is still audible in small change and in the money-changer’s stall. The broader verb of alteration is later growth on the same stem.
Borrowed from French
This is not a native Old English survival. English took the word from French in the Middle English period, after French had already been spoken in England for generations. The verb reflects Old French changier, later French changer, with the senses to alter, to exchange, and to switch. The noun came with it from Anglo-Norman chaunge and Old French change, meaning exchange, reciprocation, recompense. Early English spellings keep the French look: chaungen, chaunge.
Surviving English evidence for both parts of speech clusters around 1225. The verb is recorded in Hali Meidenhad, an alliterative homily; the noun is recorded in the Ancrene Riwle, a rule for anchoresses. Both are thirteenth-century religious texts. Anglo-Norman already had changer in the 1120s, so the French word was in use in England before English manuscripts start to show it. The path is borrowing, not inheritance from a Germanic ancestor.
English already had verbs for turning and becoming other. One of them, wendan, survives thinly as wend. Change did not invent the idea of alteration. It occupied the ordinary slot for making different and for substitution, and the older native verbs kept narrower jobs.
Latin barter, then a Celtic question
French changier continues Late Latin cambiare, an extended form of Latin cambire, to exchange or barter. In Latin the core is commercial: goods or value given for goods or value. It is not yet the loose modern English sense of any alteration at all. Medieval Latin also used the noun cambium for an exchange. English later borrowed that learned form separately as cambium, the living layer that produces new wood and bark in a stem. Cambium and change are doublets: the same Latin stock, two routes into English, two meanings.
The next step back is less settled. Dictionaries commonly mark Latin cambire as probably Celtic. A frequent reconstruction starts from Gaulish cambion, earlier *kambyom, related to Proto-Celtic *kambos, twisted or crooked. The suggested meaning path runs from bent or turned, to turned into something else, to swapped. On the crooked side sit Old Irish camm and Welsh cam. Romance languages kept the Latin verb as Italian cambiare, Spanish cambiar, Portuguese cambiar, and Romanian schimba.
That Celtic origin is a widely held view, not a closed proof. Some older accounts linked the Latin verb to Greek words for bending. Reconstructions of a deeper Indo-European root appear in several shapes, and some scholars treat the formation as possibly substrate rather than a tidy inheritance. A Gaulish form cambion does appear on the Chamalières lead tablet from Roman Gaul, but translators disagree on the line: the bent, the wrong, or the change. That inscription cannot be treated as a simple caption for the English verb. What can be said with some confidence is narrower. Latin used a word for barter that looks Celtic. French stretched the word. English borrowed the stretch.
From swapping to altering
By about 1160, Old French change named the act of giving and receiving in return. One early concrete use was the exchange of prisoners in war. Another, from around 1200, was the table or premises where money was converted. Anglo-Norman even used La Chaunge as a London name for such a place. Later twelfth-century French also used the noun for inconstancy and fickleness. Substitution and replacement are in place by about 1300. A hunting phrase, correr al change, treated the change as a shift of scent or quarry and later fed a figurative hunting sense in English.
English inherited the commercial and the general senses together. Around 1200 the verb already meant to make different and, soon after, to substitute one thing for another. By the late thirteenth century it could also mean to become different without a stated agent. From the late fourteenth century it specialized as converting a sum into smaller pieces of the same currency. Putting on other clothes is recorded from the late fifteenth century. The leftover coins returned after a purchase appear in the early seventeenth; the phrase make change is later still, in the nineteenth. Around 1400 the noun could mean a meeting place for merchants, the exchange. Early seventeenth-century biblical English used it for the passage from life to death. Bell ringing, from the same century, called any sequence other than the plain scale a change, which is why English can still ring the changes, meaning to run through permutations.
Later idioms sit on this stack rather than replacing it. For a change, from the late seventeenth century, treats novelty as a substitute for the usual. Change of heart is a nineteenth-century phrase. Change of life for the end of menstruation is recorded from the 1830s. The money sense never vanished. It became one room in a larger house.
Morphology in English is simple. The word is not a native prefix plus a native root. French built a verb with the usual -ier ending on the Latin stem. English then used that verb as a noun, as French had already done. Exchange is a related formation with an extra prefix, not a different family.
The stall sense that Romance kept
Spanish cambio and Italian cambio still often mean a rate of exchange or a bureau where currency is converted, closer to Latin barter than to a sky that turned grey. English kept that stall sense in money-changing and in the coins handed back at a counter, then let the verb become the default word for almost any becoming. The origin of the word change is that French loan: a term for swapping that English stretched until it could name difference itself.