Meanings
From thick (“friendly, intimate”), first attested in 1827 as "thick as two thieves".[1]
How to pronounce "thick as thieves":
AU
Intimate, close-knit, tight.
Example Sentences
1
Sarah and Jane are thick as thieves; they are always together.
2
Tom and Jack have been best friends for years; they are thick as thieves.
3
The two companies have a close partnership and are thick as thieves.
4
The children in the neighborhood are thick as thieves and always play together.
5
Since they both love hiking, Amy and Emily are thick as thieves when it comes to outdoor activities.
