Emily Dickinson Lexicon

COUN'TER-SIGN, v.t. [counter and sign.]

Literally, to sign on the opposite side of an instrument or writing; hence, to sign, as secretary or other subordinate officer, a writing signed by a principal or superior, to attest the authenticity of the writing. Thus charters signed by a king are countersigned by a secretary. Bank notes signed by the president are countersigned by the cashier.