An Irish phrase. Another way to tell someone to “wise up”.
To stop being so ridiculous and to come back down to Earth. Can also be said in an affectionate way, for example, when someone is being hilarious and ridiculous and you don’t agree with what they’re saying; Irish people’s tones will tell you the difference.
“I’m too sick to go to school...”
“Are you dying? No! Didn’t think so, catch yourself on and get out the front door.”
“It’s raining mammy and that means Jesus is crying.”
“Hahahahahaha catch yourself on ya eejit, it’s raining because it’s raining!”
A phrase coined during the 1960s and 1970s trucker Citizen's Band (CB) culture. It literally means "I'll contact you on the return trip." If two long-haul truck drivers regularly make opposing trips, their path will eventually meet on each iteration of the trip. This term is virtually interchangeable with catch you on the flip side.
...we're gonna back on out of here. So, keep the bugs off your glass and the bears off your tail. We'll catch you on the flip flop. This here's the Rubber Duckon the side. We gone. Bye bye.
The "flip side" is the reverse side of a vinyl record, a term often used by radio DJs. They might say "I'll catch you on the flip side" to mean they will let a particular album play through, and won't start talking again until they have to change or flip records.
"flip flop" is a variant used originally by truckers to mean a U-turn or the return trip, and may be used instead of "flip side."