When passing someone in the hall, you might say "How are you?" as a greeting, but not meaning it literally, as you don't really require an answer. Is "How are you?" (or "How's it going?", etc.) an idiom when used this way?
"Idiom" doesn't seem appropriate because that combination of words generally has the literal meaning. Is there another word for this?
Sorry if I am not making this clear. If I can clarify in some way, please ask.
Edit: Could someone explain why this question might have been voted down? Not complaining, just trying to learn.