to write your name on a document which already has the signature (= name written) of another person , especially in order to show that you are certain that the first person is who they say they are
发音
例句
1. Traveller's check need countersign. 旅行支票要复签。 2. Enclosed is our contract No. 345 in duplicate, of which please return us one copy, duly countersign. 随函附上我方第345号合同一式两分,请会签并回寄一份。