τρίειδος
From LSJ
ἑτέρως ἠδύνατο βέλτιον ἢ ὡς νῦν ἔχει κατεσκευάσθαι → otherwise they could have been constructed better than they are now (Galen, On the use of parts of the body 4.143.1 Kühn)
English (LSJ)
ον, (εἶδος IV) A composed of three ingredients, ἔμπλαστρος Aët.15.15: cf. ἑξάειδος, ἑπτάειδος, τετράειδος.