Noun: Pants, usually jeans, that are so worn out from wear and tear that the knees are completely torn out, there's strips of denim hanging of of them, and the crotch is starting to rip. They get their name because they look like they should already be in the trash can.
Anna: Dude, you're still wearing your trash can pants? I thought you pitched them a long time ago!
Tom: Well, I think they're cool! It's my fashion statement!
Anna: Fashion statement my ass! You look like you've been dumpster diving!