Late 19th century; earliest use found in The Century Dictionary. From ancient Greek ϕολιδωτός covered with scales from Hellenistic Greek ϕολιδοῦσθαι to be covered in scales, although this is apparently first attested later (from ancient Greek ϕολιδ-, ϕολίς scale, perhaps from the same Indo-European base as Russian bolona growth on trees, bolon′ soft bark, Czech blána skin) + -τός, suffix forming verbal adjectives. In later use after scientific Latin Pholidota, order name.