Where does “empyema” come from?

Empyema comes from Ancient Greek ἐμπύημα, a noun formed with the suffix -μα from ἐν meaning "in," ultimately from Proto-Indo-European h₁én.

empyema (English): A collection of pus within a naturally existing...

Definitions

Step	Language	Word	Meaning
1	Ancient Greek	ἐμπύημα	Gathering or abscess, especially internal, of the...
2	Ancient Greek	ἐμπυέω	To suppurate
3	Ancient Greek	ἐν	in, on, at; among; in, at, or during the time of
4	Ancient Greek	δέρμα	skin, hide
5	Ancient Greek	γλυφή	carving, carved work; hole cut
6	Ancient Greek	-ῐ́ᾱ	{{l\|en\|-ia}}; "suffix forming abstract feminine...
7	Proto-Indo-European	-íh₂	—
8	Proto-Indo-European	-h₂	Creates collective nouns, which refer to groups...