Meaning of "redstart" in the English dictionary

Redstarts are a group of small Old World birds. They were formerly classified in the thrush family, but are now known to be part of the Old World flycatcher family Muscicapidae. They are currently treated in four genera, the true redstarts Phoenicurus, the closely related genera Chaimarrornis and Rhyacornis, and the less closely related genus Hodgsonius. These are insectivorous ground feeding birds, most of which have the red tail which gives the group its name; "start" is the modern English reflex of Middle English stert, Old English steort, tail of an animal. Most species are migratory, with northern species being long-distance migrants and more southerly species often being altitudinal migrants breeding at high altitude and moving lower down in winter. They are small insectivores, the males mostly brightly coloured in various combinations of red, blue, white, and black, the females light brown with a red tail.