As thick as thieves — #idiom #meaning
Meaning:
- (of two or more people) very close or friendly; sharing secrets
- very close and secretive
- intimate, closely allied
Origin:
This term uses thick in the sense of “intimate,” a usage that is obsolete except in this simile. The association of thieves with conspiratorial and secretive language was well established in England in the 18th century. Many of those on the fringes of society, for example poachers, homosexuals, street hawkers and thieves, used secret words and phrases to converse furtively amongst themselves.
Examples:
1) All among the trees, the birds are thick as thieves and noisy as conventioneers.
2) I'm sure she tells Ruth everything we say - they're as thick as thieves, those two.
