The Collaborative International Dictionary of English v.0.48:

Gymnonoti \Gym`no*no"ti\ (j[i^]m`n[-o]*n[=o]"t[imac]), n. pl.
   [NL. fr. Gr. gymno`s naked + nw^tos the back.] (Zool.)
   The order of fishes which includes the Gymnotus or electrical
   eel. The dorsal fin is wanting.
   [1913 Webster]