sheldrake

noun, plural shel·drakes, (especially collectively) shel·drake.

1. any of several Old World ducks of the genus Tadorna, certain species of which have highly variegated plumage.
2. any of various other ducks, especially the goosander or merganser.

n.early 14c., from sheld- “variegated” + drake “male duck.” First element cognate with Middle Dutch schillede “separated, variegated,” West Flemish schilde, from schillen (Dutch verschillen “to make different”), from Proto-Germanic *skeli-, from PIE root *(s)kel- (1) “to cut” (see scale (n.1)). This is the origin considered most likely, though English sheld by itself is a dialect word attested only from c.1500. OED finds derivation from shield (n.), on resemblance to the patterns on shields, “improbable.”