H2O

noun
\ ˈāch-ˈtü-ˈō How to pronounce H{inf}2{/inf}O (audio) \

Definition of H2O

: water sense 1a American lawns and gardens drink up H2O at alarming rates, especially in the dry West, where more than 50% of residential water is used for landscaping.— Bryan Walsh

First Known Use of H2O

1879, in the meaning defined above

Learn More About H2O

Dictionary Entries Near H2O

H2

H2O

H3

Statistics for H2O

Cite this Entry

“H2O.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/H2O. Accessed 18 Aug. 2022.

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