Pum is the act of tucking your dickin between your legs before ejaculation halting the cum but maintaining the orgasm only to later let the cum out in your next piss.
In the islands of Trinidad and Tobago a 'pum' is the short and more commonly used word for a pumse (pronounce with the short sounding 'u' )It is casually used to refer to the passing of gas or flatus.What the world knows as a fart.
Simone:Did you smell that pum in the bus?
Bill:Did you pum?
Lisa:Did you hear that?,sounded like sombody pum.