When an excited dog closes their mouth too soon when trying to catch a ball, causing the ball to bounce away off their nose
John- How's Sammy with the ball these days? Is she able to catch it?
Dave- Nah, gets so excited that when I throw the ball at her, she premature catchulates all over the place... She has a real bad case of premature catchulation.
The act of involuntarily and immediately regurgitating cum all over a man’s penis during or directly after orgasm while attempting to swallow. This can happen from either a failed swallow or by the man’s penis being too deep (or being forced too deep) into the mouth of the person giving the blowjob.
Kate: I thought I had it, but when he started to cum he pushed in deeper and I couldn't hold it all and totally cumchucked back on his cock and bed.
Robin: Oh my God, was he pissed?
Kate: A little, but he was still in postcoital bliss, so he was cool with it.