tap water

WordReference Random House Unabridged Dictionary of American English © 2026

tap′ wa′ter, 

1. water, obtained directly from a faucet or tap, that has not been purified, distilled, or otherwise treated.

• 1880–85

Collins Concise English Dictionary © HarperCollins Publishers::

tap water noun

1. water drawn off through taps from pipes in a house, as distinguished from distilled water, mineral water, etc