any of various small, yellow or yellowish-green Eurasian finches of a genus (Serinus) that includes the canary, esp. a European species (S. serinus)
See serin in American Heritage Dictionary 4
(sĕrˈĭn)
noun
Any of several Old World finches of the genus Serinus having yellowish plumage, especially a European species (S. serinus) closely related to the canary.