/kloʊz/ (verb), /kloʊs/ (adjective/adverb)
[verb] To move something so that it covers an opening, or to bring something to an end. As an adjective, it describes something that is very near in distance, time, or relationship.
Every time you 'close' a door, you are echoing a Latin word that once meant 'to shut in' an entire Roman army.
The word 'close' begins its life in Latin, with the verb claudere, meaning 'to shut' or 'to enclose.' This was a robust, practical word in classical Latin — used for shutting gates, closing ranks of soldiers, and ending arguments. Its past participle, clausus, meant 'shut' or 'enclosed,' and from this single root, Latin gave the world an extraordinary family of descendants that would scatter across a dozen modern languages.
As the Roman Empire faded and Vulgar Latin evolved in the hands of ordinary speakers across France, claudere softened in pronunciation. The 'cl-' sound shifted and the word became closer to clore or clorre in Old French, which carried the same core meaning: to shut, to seal, to finish. This Old French form entered English in the 13th century, during the long centuries after the Norman Conquest when French vocabulary was flowing steadily into the English language. English speakers adopted it enthusiastically, and 'close' quickly established itself as a natural part of everyday speech.
The adjective sense — meaning 'near' — developed slightly differently. It came from the Old French adjective clos, itself from Latin clausus, meaning 'enclosed.' The idea was that something enclosed or shut in was, by definition, kept near and tight. A 'close' space was a shut-in space, a confined one. Over time, the sense of physical confinement expanded into a broader idea of nearness: two people who are emotionally 'close' are, in a sense, enclosed together within a shared bond. This metaphorical leap happened gradually through the 14th and 15th centuries.
The Latin root claudere was extraordinarily fertile. It gave English — always through careful chains of transmission — words like 'enclose' (Latin claudere → Old French enclos → English enclose), 'disclose' (Latin dis + claudere → Old French desclore → English disclose), and 'clause' (Latin clausa, a closed or concluded section, → Old French clause → English clause). Even 'cloistered' monks living in a cloister owe their word to the same root: Latin claudere → Latin claustrum (an enclosed place) → Old French cloistre → English cloister. The word 'exclude' follows yet another path: Latin ex + claudere → Latin excludere → Old French exclure → English exclude.
Perhaps most surprisingly, the word 'slot' — as in a thin opening — is also a distant cousin, and the word 'sluice' (a gate that controls water) traces back through Old French escluse to Latin exclusa, itself from excludere. Even 'closet' is a direct descendant: Old French closet was simply a small enclosed space, a diminutive of clos. So when you step into a closet or shut a sluice gate, you are, without knowing it, performing a gesture that claudere would have recognized two thousand years ago.
Today 'close' sits comfortably at the center of English, used hundreds of times a day without a thought for its Latin soldier-ancestry. It has given rise to phrasal verbs like 'close down,' 'close in,' and 'close up,' as well as the noun form — a 'close' in British English can mean an enclosed courtyard or a dead-end street, again echoing that original sense of a space that is shut off from the wider world. Few words carry so much history so lightly.