Countersign1. (v. t.) To sign on the opposite side of (an instrument or writing); hence, to sign in addition to the signature of a principal or superior, in order to attest the authenticity of a writing.
2. (n.) The signature of a secretary or other officer to a writing signed by a principal or superior, to attest its authenticity.
3. (n.) A private signal, word, or phrase, which must be given in order to pass a sentry; a watchword.
Thesaurus Entries
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