pass muster/pass mustard

This is one of those errors that occurs because you pronounce it the way you hear it. See Saturday's post. . .same type of thing.

To "pass muster" means to have passed the test; to be accepted. Nobody knows what the heck muster is, so it's assumed it must be "mustard" since the words are so close.

"Muster" actually has its roots in the military. It's an assembly of troops awaiting inspection. Obviously, if you're acceptable, you've "passed muster."

"Pass mustard" is something you would say to someone who's been nice enough to give you a hot dog. Of course you wouldn't just say, "Pass mustard." You would need at least an article sandwiched in there, maybe "the," unless you're trying to sound like Frankenstein.