A universal euphemism that tends to have sexual innuendos but can be attributed to any activity. It's meaning is subjective to the nature of the conservation at hand.
"I'm sorry, Bob, but your girlfriend and I yeehaw'd last night"
"Why did you take so long to get in the car, were you yeehawing?"
"Yes, Joe. I yeehaw'd until my eyes bled"
"I'm gonna yeehaw, go to the gym, and then read my book"
"Sounds like a plan, Jill!"