underwater

adjective

un·​der·​wa·​ter ˌən-dər-ˈwȯ-tər 

-ˈwä-

1

: lying, growing, worn, performed, or operating below the surface of the water

underwater plants

2

: being below the waterline of a ship

3

a

: having, relating to, or being a mortgage loan for which more is owed than the property securing the loan is worth

b

: having, relating to, or being a stock option for which the price of the option is higher than the current market value of the stock

underwater adverb

Synonyms

• aquatic
• submarine
• submerged
• sunken

Examples of underwater in a Sentence

underwater plants don't require as much light to grow as surface plants

a vessel designed for underwater exploration

Recent Examples on the Web

Trump's approval ratings are underwater in Virginia, currently governed by Republican Glenn Youngkin, where 46 percent of voters approve of the president's job—down one percentage point since last month—and 52 percent disapprove. —Nick Mordowanec, MSNBC Newsweek, 18 June 2025

Curious, the mariners decided to investigate using an underwater camera. —Sarah Kuta, Smithsonian Magazine, 18 June 2025

In another sign of a thinning primary field, Michael Blake, a fellow back-of-the-pack mayoral candidate, is also underwater, reporting being in the red by about $34,000 after raising only about $22,000 in the latest window. —Chris Sommerfeldt, New York Daily News, 14 June 2025

The president’s office tower on Wall Street appears to be underwater. —Dan Alexander, Forbes.com, 12 June 2025

Word History

First Known Use

1627, in the meaning defined at sense 1

Rhymes for underwater

• annunciator
• imprimatur
• backwater
• bathwater
• blackwater
• breakwater
• deepwater
• edgewater
• feedwater
• floodwater
• freshwater
• granddaughter

Kids Definition

underwater

adjective

un·​der·​wa·​ter ˈən-dər-ˈwȯt-ər 

-ˈwät-

: lying, growing, worn, performed, or operating below the surface of the water

underwater plants

an underwater cave

underwater

-ˈwȯt-

-ˈwät-

adverb

Legal Definition

underwater

adjective

un·​der·​wa·​ter

1

: owing more on a mortgage loan than the property securing the loan is worth

underwater homeowners

2

: being or relating to a mortgage loan in which more is owed than the property securing the loan is worth

underwater mortgages

underwater properties