ˈȯrˌläp- noun
Etymology: orlop from Middle English overlop deck of a single-decker, from Middle Low German overlōp, literally, something that overleaps, from over + lōp leap, from lōpen to leap, run; akin to Old High German ubar over and to Middle Dutch lōpen to run — more at over , leap
1. : the deck below the lower deck : the lowest continuous deck in a ship having more than three decks — see deck illustration
2. : the lowest deck in a ship