eristalis
From LSJ
ἀπὸ τῶν καρπῶν αὐτῶν ἐπιγνώσεσθε αὐτούς → ye shall know them by their fruits, by their fruits ye shall know them, by their fruits you shall know them, you will know them by their fruit
Latin > English (Lewis & Short)
ĕristălis: is, f.,
I an unknown precious stone, Plin. 37, 10, 58, § 160 (dub.—Jan. erythallis).