Pōr’toise, n.

(pōr’tiz), n. [Perhaps from O. Fr. porteis, portative, portable.] (Naut.) The gunwale of a ship.

To lower the yards a portoise or a portlast (Naut.), to lower them to the gunwale.—To ride a portoise, to have the lower yards and top-masts struck or lowered down, when at anchor, in a gale of wind.