TL;DR: There is a Far Side about the spikes on a dinosaur tail being called the Thagomizer ("after the late Thag Simmons"). Scientists realized there wasn't a

TL;DR: There is a Far Side about the spikes on a dinosaur tail being called the Thagomizer ("after the late Thag Simmons"). Scientists realized there wasn't a name for that, so they started using "Thagomizer".