watertight

adjective

wa·​ter·​tight ˌwȯ-tər-ˈtīt 

ˌwä-

1

: of such tight construction or fit as to be impermeable to water except when under sufficient pressure to produce structural discontinuity

2

: leaving no possibility of misconstruction or evasion

a watertight lease

watertightness noun

Examples of watertight in a Sentence

The doors are all watertight.

The evidence against the defendant was watertight.

Recent Examples on the Web

The Woods Hole underwater acoustic system includes off-the-shelf components in a watertight Pelican case. —IEEE Spectrum, 20 Nov. 2024

The presence of a watertight strategic rationale for projects, such as arming NATO allies against the Soviet Union, helped to quell those concerns, at least temporarily. —Ashlyn Anderson, Foreign Affairs, 11 Feb. 2016

Elsewhere, all the seasickness and disorientation — down to the sound of the bullets and the code names of Omaha Beach sectors — were factually watertight. —Tomris Laffly, EW.com, 6 July 2024

This is literally making sure the car is watertight and noise proof because sealing also stops noise getting in. —WIRED, 15 June 2023

Word History

First Known Use

15th century, in the meaning defined at sense 1

Kids Definition

watertight

adjective

wa·​ter·​tight ˌwȯt-ər-ˈtīt 

ˌwät-

1

: made to keep water out

a watertight compartment

2

: allowing no possibility for doubt or uncertainty

a watertight case against the accused