In tarot culture
When you watch a reading to find something out about someone else from their signs perspective.
“My ex is an Aries so I cross watched the Aries reading.”
“I’m an Aquarius but I’m watching Leo’s reading because that’s my friends sign, I’m cross watching by watching Leo.”
“She’s a cross watcher. She watches other people’s signs.”
a random insult that makes no sense but still stings
"My friend Levi called me a cross-ribbed ape watcher."
"What does that even mean?"
"No idea, but long story short, I'm never asking him how to spell orange again"