A thrush is a small brown or gray speckled songbird. Thrushes are known for their loud, musical songs.
There are two main meanings of the noun thrush, with two completely different origins. The thrush that flies around singing a lovely song gets its name from a Germanic root, while another thrush, a type of infection, comes from a Scandinavian source. This second thrush is a yeasty fungal infection that's common in the mouth and throat of babies, appearing as distinct white patches.