TREADS THE BOARDS is an idiom which means to perform on stage, usually referring to an actor or actress. The crossword solutions SURFS (5 letters) and ACTS (4 letters) are related to this phrase. SURFS is a verb meaning to ride the waves of the sea, while ACTS is a verb meaning to perform a role in a play or movie. Together, these two words form the phrase TREADS THE BOARDS, which is used to describe someone who performs on stage.