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Synonyms

thick as thieves

Idioms  

  1. Intimate, closely allied, as in The sisters-in-law are thick as thieves. This term uses thick in the sense of “intimate,” a usage that is obsolete except in this simile. [Early 1800s]

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.

"They were thick as thieves," explains Harsha Evangeli, who taught the teenager art.

From BBC • Mar. 13, 2025

Swifties believe the lyrics “Now she gets the house, gets the kids, gets the pride / Picture me, thick as thieves with your ex-wife,” are actually a reference to West and Kardashian’s divorce, not Braun’s.

From Los Angeles Times • Oct. 21, 2022

“They were literally thick as thieves in the sense of sticking together and having each other’s back. They were best friends as well.”

From Washington Times • Apr. 7, 2022

We were thick as thieves, the two of us.

From New York Times • Feb. 22, 2022

The teachers, the pupils, the principal, everyone at school knew: Teddy and Trevor, thick as thieves.

From "Born a Crime: Stories from a South African Childhood" by Trevor Noah

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

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.