COMMON If you cut your teeth doing something, you get your first experience of it and learn how to do it. He plans to cut his teeth on demanding theatre parts before making the break for TV and film. He cut his teeth in the sixties as director of Edinburgh's Traverse Theatre. Note: This expression can be varied by adding an adjective before teeth to show what sort of experience was gained. He had cut his editorial teeth on the London Evening Standard. Note: When a child cuts a tooth, the tooth begins to appear through the gum.