Definitions for gnatcatcherˈnætˌkætʃ ər
Random House Webster's College Dictionary
any of various small, insect-eating New World songbirds of the genus Polioptila (subfamily Silviinae), having a long, mobile tail.
Origin of gnatcatcher:
very small North American and South American warblers
A member of any of various species of small passerine birds found in North America and South America, close relatives of the wrens.