teal (n.)

"small freshwater duck," early 14c., of uncertain origin, probably from an unrecorded Old English word cognate with Middle Dutch teling "teal," Middle Low German telink, from West Germanic *taili. As the name of a shade of dark greenish-blue resembling the color patterns on the fowl's head and wings, it is attested from 1923 in clothing advertisements.

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Definitions of teal from WordNet
teal (n.)
a blue-green color or pigment;
Synonyms: bluish green / blue green
teal (n.)
any of various small short-necked dabbling river ducks of Europe and America;
teal (adj.)
of a bluish shade of green;
Synonyms: bluish green / blue-green / cyan