The definition of underwater is something that is used or done under water.(adjective)
An example of something underwater is an reef that is submerged in water.
Underwater is defined as to be submerged in water.(adverb)
An example of underwater is where deep sea divers are when they dive.
Underwater means that you owe more on your home or property than it is worth.(adjective)
An example of being underwater is having the value of your house drop below the amount of the mortgage.
See underwater in Webster's New World College Dictionary
See underwater in American Heritage Dictionary 4
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