Source : Webster's Revised Unabridged Dictionary (1913)

Lernean \Ler*ne"an\ (l[~e]r*n[=e]"an), n. [See {Lern[ae]a}.]
   (Zo["o]l.)
   One of a family ({Lern[ae]id[ae]}) of parasitic Crustacea
   found attached to fishes and other marine animals. Some
   species penetrate the skin and flesh with the elongated head,
   and feed on the viscera. See Illust. in Appendix.