The description of the 1st-level spell Thunderous Smite (PH 282) states the following:
[...] Additionally, if the target is a creature, it must succeed on a Strength saving throw or be pushed 10 feet away from you and knocked prone.
How is a creature defined? Without this spell, I would have defined literally everything as a creature, but then why would this distinction exist?
Just so you can't push a boulder away, which 99% of DMs wouldn't allow this spell to do anyway? That seems odd to me.
I couldn't find anything online that defines creatures as something other than everything, so I came here hoping that someone would have an answer.