Clypeus

clypeus \ˈkli-pē-əs\ noun: a plate on the anterior median aspect of an insect's head (plural clypei \-pē-ˌī, -pē-ˌē\)

Etymology: New Latin, from Latin, round shield

I know what you’re thinking: “Clypeus? Clypeus? Tell us something we don’t know!” What can I say? They can’t all be five-dollar words.