ˌsocial seˈcurity BrE AmE noun [uncountable]
1 . British English government money that is paid to people who are unemployed, old, ill etc SYN welfare American English :
social security benefits
be/live on social security (=be receiving money from the government)
2 . Social Security a US government programme into which workers must make regular payments, and which pays money regularly to old people and people who are unable to work
⇨ National Insurance