C1idiominformalpeopleIELTS-friendly
thick as thieves
USUK
very close friends who share secrets
Often with 'as' in front: 'as thick as thieves'. Friendly, despite 'thieves'; it suggests the friends share secrets.
In context
Those two have been as thick as thieves since primary school.
The cousins are thick as thieves and always whisper at family dinners.
More idioms about people
- a chip off the old blocka child who is very like one of their parents in character or skills
- a cold fishsomeone who seems unfriendly and does not show feelings
- a drama queensomeone who reacts to small problems as if they were very serious
- a fair-weather friendsomeone who is your friend only when things are going well for you
- a friend in need is a friend indeeda person who helps you when you are in trouble is a true friend