The story
Rhyming compound of comp (“computer; i.e computer-controlled opponent”) + stomp (“extremely uneven victory”), from the tendency of such games to be played casually for entertainment.
Etymology from Wiktionary, CC BY-SA 4.0.
comp stomp
Today it means: A cooperative game format typical to competitive player-versus-player video games, such as real-time strategy games, where a number of human players instead team up against one or more computer-controlled opponents. Full definition →