From WordNet (r) 2.0 (August 2003) [wn]:
eel
n 1: the fatty flesh of eel; an elongate fish found in fresh
water in Europe and America; large eels are usually
smoked or pickled
2: voracious snakelike marine or freshwater fishes with smooth
slimy usually scaleless skin and having a continuous
vertical fin but no ventral fins
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Eel \Eel\, n. [AS. ?l; akin to D., G., & Dan. aal, Icel. [=a]ll,
Sw. [*a]l.] (Zo["o]l.)
An elongated fish of many genera and species. The common eels
of Europe and America belong to the genus Anguilla. The
electrical eel is a species of Gymnotus. The so called
vinegar eel is a minute nematode worm. See Conger eel,
Electric eel, and Gymnotus.
[1913 Webster]