Main Entry: coun·ter·sign

Pronunciation: \-ˌsīn\

Function: noun

Date: 1591

1 : a signature attesting the authenticity of a document already signed by another
2 : a sign given in reply to another; specifically : a military secret signal that must be given by one wishing to pass a guard

— countersign transitive verb

— coun·ter·sig·na·ture \ˌkau̇n-tər-ˈsig-nə-ˌchu̇r, -chər, -ˌtyu̇r, -ˌtu̇r\ noun