Dictionary
wa•ter•tight
Pronunciation: (wô'tur-tīt", wot'ur-), [key]—
adj.
1. constructed or fitted so tightly as to be impervious to water:
The ship had six watertight compartments.
2. so devised or planned as to be impossible to defeat, evade, or nullify:
a watertight contract; a watertight alibi. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.