Definition of "flycatcher"

Any of many kinds of birds of the family Muscicapidae, of Africa, Europe, and Asia, that catch insects in flight; an Old World flycatcher.  examples

Any of many kinds of similar birds of various families, such as Tyrannidae (the New World flycatchers of the Americas), Tityridae, Stenostiridae, Monarchidae, Petroicidae, etc.  examples