Sigh. Amazing how difficult something simple can be! I thank all for guesses, but this really is an 'on the bus, off the bus' question.

Thanks for Trojan Asteroids, but no: I KNOW a Centaur is the term for an asteroid/comet (just as I KNOW a human/horse hybrid is a centaur), the question is: when they chose the name for the class or group of items or what-have-you which the latter term centaur represents in homage to the former class of objects, what is the RHETORICAL TERM for engaging in such an homage?

The etymology of chapel is closer, but I'd still believe that the origin of that word as a general term from one specific example and ... something else-y is NOT a parallel. But again: thank you for playing and I hope someone knows the actual answer! Argghhh!