Pronunciation: (top'sīd"),[key] —n. 1. the upper side.
2. Usually, topsides.Naut.the outer surface of a hull above the water.
3. the most authoritative position or level.
4. Chiefly Brit.a cut of beef similar to a U.S. rump roast. Cf. silverside (def. 1).
5. Brit.the top or outer side of a round of beef; beef from the outer thigh of a butchered cow.
—adj. 1. of, pertaining to, or located on the topside.
2. of the most authoritative rank.
—adv. 1. Also,top'sides".up on the deck: He left the engine room and went topside. 2. to, toward, or at the topside.