type of fish, c.1500 (early 13c. as a surname), from grund "ground" (see ground (n.)) + -el. Cf. Old English gryndle "herring."
Online Etymology Dictionary, © 2010 Douglas Harper
Examples from the Web for grundel
The name would have a parallel in the Modern English grindle, grundel, German grundel, a fish haunting the bottom of the water.Beowulf
R. W. Chambers