Social Security number

American  

[soh-shuhl si-kyoor-i-tee nuhm-ber] / ˈsoʊ ʃəl sɪˈkjʊər ɪ ti ˌnʌm bər /

noun

1. a unique nine-digit number assigned to each U.S. citizen and sometimes also given to resident non-citizens, used by the government for Social Security taxes, program eligibility, etc. SSN

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Etymology

Origin of Social Security number

First recorded in 1935–40

Example Sentences

See Examples For:

Social Security number

That’s because the IRS form parents use to claim the Child and Dependent Care Credit will expect the name, address and Social Security number or Employer Identification Number of the care provider.

From MarketWatch ● Jul. 6, 2026

This elaborate scam includes setting up a time for an interview and then being asked for personal information such as a copy of your W-2 or your Social Security number.

From Los Angeles Times ● Jun. 11, 2026

The third time, their Social Security number will be flagged and they will be permanently banned from IPO access.

From MarketWatch ● Jun. 11, 2026

Babies born from 2025 to 2028 who are American citizens and have a Social Security number are eligible for the seed money.

From Barron's ● May 28, 2026

Curiously, when McCandless applied for the McDonald’s job, he presented himself as Chris McCandless, not as Alex, and gave his employers his real Social Security number.

From "Into the Wild" by Jon Krakauer