Definition & Meaning of "nonce"in English

What is the origin of the term "nonce" and how is it used?

"Nonce" is a British English slang term that emerged in the late 20th century, primarily in prison and criminal contexts. Its exact origin is uncertain, but it is believed to have arisen in the 1970s–1980s as prison slang for a sex offender, especially one who abuses children. The term is used to identify and stigmatize individuals convicted or accused of such crimes. It is highly derogatory, socially and morally loaded, and extremely offensive, almost always used in informal, criminal justice, or media contexts rather than polite conversation.