Quiz: Remember the definition of mal de mer?
early 15c., "acceptance, reception, approval," from Latin admissionem (nominative admissio) "a letting in," noun of action from past participle stem of admittere (see admit). Meaning "an acknowledging" is from 1530s. Sense of "a literal act of letting in" is from 1620s. As short for admission price, by 1792.