Definition of "deep water"

deep water

noun
countable and uncountable, plural deep waters
1. Used other than figuratively or idiomatically: see deep,‎ water.
2. Waters suitable for deep-draft ships, especially ocean-going.
  Quotations
  But deep water was not secured until 1926, when Corpus Christi dug itself out 21 miles to the sea.
  1940, Federal Writers' Project, Texas: A Guide to the Lone Star State, page 71
3. (idiomatic) A difficult or embarrassing situation.