what is a wren
Full Definition of WREN. 1. : any of a family (Troglodytidae) of small typically brownish oscine singing birds; especially: a very small widely distributed bird (Troglodytes troglodytes) that has a short erect tail and is noted for its song. 2. : any of various small singing birds resembling the true wrens in size and habits.. : any of a family (Troglodytidae) of small typically brownish oscine singing birds; especially: a very small widely distributed bird (Troglodytes troglodytes) that has a short erect tail and is noted for its song.