hair-splitting adjective 1noun 1forms 3 adjective1 •Of or characterized by hair-splitting, seeking or having exceedingly small differences, fine details, and/or edge cases of no seeming importance, concerning or concerned with minutiae.Dick's Tribune poked endless fun at the hair-splitting sectarianism of the various Trotskyist groups jostling on the fringes of the Labour party at that time. — 2006 noun1 •The act of considering or arguing about exceedingly small differences, fine details, and/or edge cases of no seeming importance, worrying about minutiae. formshair-splittings · more hair-splitting · most hair-splitting