ὑπόχαλκ-ος · hypochalk-os — LSJ
containing a mixture of copper, bronze gilt
containing a mixture of copper, Pl. R. 415b; κανοῦν χρυσοῦν ὑπόχαλκον bronze gilt, IG 2(2).1407.21; ὑπόχαλκον δέ σου τὸ χρυσίον Com.Adesp. (?) ap. Suid. s.v. ὑπόχαλκον: metaph., Plu. Lib.educ. 2.1b, Adul. 65a: cf. ὑπάργυρος, etc.
2 sounding like copper
sounding like copper, ὑ. ἠχὼ φέρειν Philostr. VA 3.8.
3 of a copper colour
of a copper colour, ζῷον ὑπόχαλκον τὴν μορφήν (sc. the οἶστρος or μύωψ) Sch. Od. 22.299.