Entry 1 sense Webster, 1913 After-sails /(ăf"tẽr*sālz`)/ · Aft·er-sails · IPA 01 n. The sails on the mizzenmast, or on the stays between the mainmast and mizzenmast. 1. The sails on the mizzenmast, or on the stays between the mainmast and mizzenmast.(Naut.)