in deep

Idioms

Seriously involved; far advanced. For example, He was in deep with the other merchants and couldn't strike out on his own , or She used her credit cards for everything, and before long she was in deep .
in deep water . Also, in over one's head . In trouble, with more difficulties than one can manage, as in The business was in deep water after the president resigned , or I'm afraid Bill got in over his head . These metaphoric expressions transfer the difficulties of being submerged to other problems. The first appears in Miles Coverdale's 1535 translation of the Book of Psalms (68:13): “I am come into deep waters.” The second, which also can signify being involved with more than one can understand, dates from the 1600s. Also see over one's head .

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Catsimatidis made millions from buying New York real estate on the cheap in the 1970s when the city was in deep economic trouble.

From Los Angeles Times • Apr. 22, 2026

“No one had ever filmed a tiger killing in deep water before,” Thapar recounts.

From The Wall Street Journal • Apr. 21, 2026

This is the man who kept Newcastle up in 2022 after taking over a winless side in deep relegation trouble only a few months previously.

From BBC • Apr. 18, 2026

The rock layer where the wrinkles formed originated in deep ocean water, nearly 600 feet below the surface.

From Science Daily • Apr. 3, 2026

Izio would walk me home on those nights, in deep, cold snow lit golden by the streetlights.

From "The Light in Hidden Places" by Sharon Cameron

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023