any one of numerous species of singing birds belonging to turdus and allied genera. they are noted for the sweetness of their songs.-any one of numerous species of singing birds more or less resembling the true thrushes in appearance or habits; as the thunderbird and the american brown thrush (or thrasher). see brown thrush.-an affection of the mouth, fauces, etc., common in newly born children, characterized by minute ulcers called aphthae. see aphthae.-an inflammatory and suppurative affection of the feet in certain animals. in the horse it is in the frog.