A man or woman who sees you working the room, getting your flirt on, and remains in the background until the precise moment when BAM!-you have used up all your slutty powers and are drained and then they move in and take it to the next level-out slutting you.
Did you see Gina jump up on the bar after I did? OMG that strip tease was straight up under-cutter slutter.
Commonly referred to in organised fighting, a weight cutter is a competitor who seeks to get into a lower (easier) weight class by dehydrating with diuretics before weighting in, then rehydrating before fight day.
Weight cutters therefore get an unfair advantage over those who weigh in at their natural weight.
"That guy's gotta be 165lbs right now, so if he got into the 155lb class this morning he may be a weight cutter."