social insurance number
/ˌsəʊʃl ɪnˈʃʊərəns nʌmbə(r)/
/ˌsəʊʃl ɪnˈʃʊrəns nʌmbər/
Etymology
Latin (socius → socialis)Old French (assurer → insurance → Old French enseurer)Latin (numerus → number)Canadian English (social insurance number, 1964)
The term 'social insurance number' was introduced in Canada in 1964 when the Canada Pension Plan began. 'Social insurance' refers to the government system that provides financial protection to citizens, and 'number' refers to the personal identifier assigned to each individual in the system. The abbreviation SIN is commonly used in everyday Canadian English.