Social Security number

American  

[soh-shuhl si-kyoor-i-tee nuhm-ber] / ˈsoʊ ʃəl sɪˈkyʊər 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

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

They need to be U.S. citizens with a valid Social Security number.

From MarketWatch • May 28, 2026

Children born between 2025 and 2028 who are U.S. citizens and have a Social Security number are eligible for $1,000 in seed money from the federal government.

From The Wall Street Journal • May 27, 2026

I plugged dad’s Social Security number into “Where’s My Refund?” at irs.gov.

From The Wall Street Journal • Feb. 8, 2026

Also, if you don’t already have an employment authorization card or a Social Security number, you can obtain both as part of your adjustment-of-status application.

From "Americanized" by Sara Saedi