The Laboratorium : Any Classicists in the House?

What’s the pural of “ethos?” It’s “ethoi,” right?

UPDATE: No! It’s a neuter noun, despite ending in “os.” That means the plural is “ethea.” Thanks, Seth!

UPUPDATE: No again! The plural is “ithi,” according to an actual speaker of modern Greek, who assures me that the form is the same in classical Greek, as well. I think “ethe” is also a plausible English transliteration. Here’s the morphological analysis. Seth appears to have found an archaic variant used by Homer.