I dunno? Maybe because there's a mixed of enemies in a single battle with different elemental affinities (absorb/immune) so it gets confusing and I think I relied too much on her commentary.
They both mean you shouldn't attack them with that, so it's hardly confusing. Same with Repel.
Think of it this way. We have three buttons on a wall. One will impale you with spikes, one will explode, and the last sets you on fire. They do different things, but none of them do you any good. I could slap a "Do not push this button" sign on all of them and regardless of what will actually happen it gets the job done.
If you want to know which enemy is which, get to analyzing.
Official Lopunny of the Black 2 Boar . . . wait, how did THAT happen?!?