Dictionary.com
Thesaurus.com
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 This term uses thick in the sense of “intimate,” a usage that is obsolete except in this simile.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.

“But behind the scenes? Heidi and I were still thick as thieves, scheming side by side, laughing at how easy it was to keep the world guessing and the checks coming in.”

From Los Angeles Times • May 21, 2026

"They're all thick as thieves communicating, and that's an amazing feeling."

From BBC • Apr. 9, 2026

“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

“Maybe. All I know is your gram and Madeline were thick as thieves after your gram came back to school.”

From "How to Disappear Completely" by Ali Standish

Vocabulary.com logo
by dictionary.com

Look it up. Learn it forever.

Remember "thick as thieves" for good with VocabTrainer. Expand your vocabulary effortlessly with personalized learning tools that adapt to your goals.

Take me to Vocabulary.com