expression n1 : an act, process, or instance of representing or conveying in words or some other medium
: speech [protected under the First Amendment]
2 : a mode or means of expressing an idea, opinion, or thought NOTE: An expression is protectible under copyright law, but an idea is not.
Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.