Nonce

Part of speech: noun, adjective

Pronunciation: /nɒns/

Definitions

1. A word or expression coined for a single, specific occasion or purpose
2. A term devised for a unique instance or event that typically serves a temporary function
3. A word or phrase created for a particular occasion or use that is not permanent ; a term used infrequently or only once in its context

Etymology: The most surprising thing about "nonce" is that its modern sense of "for the time being" grew from a phrase that meant "for the once." Middle English "to þen anes" and "for þen anes" meant "for the one occasion," and speakers gradually misread the phrase as a single word, "nonse" or "nones," which was then reshaped into "nonce." The sense of a one-off, made-for-the-occasion item came straight out of that original idea of a single instance. The word took on a darker, unrelated life in British criminal slang, where it became a term for a child molester. Its origin there is unknown. Proposed sources include a dialect word "nonse" meaning a stupid or worthless person, and "nance," a slur for an effeminate man, though neither can be firmly shown to predate the criminal sense. That slang sense is still the one most often met today in British prison and tabloid usage, and it sits uneasily beside the older, innocent meaning. The term also became a cryptography word in 1975, used for a value that is employed only once in an encryption scheme. The popular claim that it abbreviates "number used once" is probably wrong.

Synonyms: for now, temporary, pro tem, for the time being, short-term

Antonyms: permanent, enduring, lasting, everlasting, eternal