[ waw-ter-tahyt, wot-er- ]
/ ˈwɔ tərˌtaɪt, ˈwɒt ər- /


constructed or fitted so tightly as to be impervious to water: The ship had six watertight compartments.
so devised or planned as to be impossible to defeat, evade, or nullify: a watertight contract; a watertight alibi.

Origin of watertight

Middle English word dating back to 1350–1400; see origin at water, tight

Related forms

wa·ter·tight·ness, nounnon·wa·ter·tight, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for watertightness

  • Exceptionally good concreting is essential in tank work if watertightness is to be secured.

    Concrete Construction|Halbert P. Gillette
  • Again the work has to be done uniformly well, not only for appearance sake but because of the necessity of watertightness.

    Concrete Construction|Halbert P. Gillette

British Dictionary definitions for watertightness


/ (ˈwɔːtəˌtaɪt) /


not permitting the passage of water either in or outa watertight boat
without loopholesa watertight argument
kept separate from other subjects or influencesdifferent disciplines are often thought of in watertight compartments

Derived Forms

watertightness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012