Rare the lowest deck of a ship with four or more decks
Webster’s New World College Dictionary, Fourth Edition, compiled by the
editors of Webster’s New World Dictionaries. Copyright © 2010 by Houghton
Mifflin Harcourt. Published by Houghton Mifflin Harcourt. All rights reserved.
Word origin of 'orlop'
< Du overloop
over + loopen,
to run (see leap
): so called because it covers the hold