Vireo
 This article is about the bird family. For the bird genus see Vireo (genus) For other uses see Vireo (disambiguation).The vireos /ˈvɪri.oʊz/ make up a family Vireonidae of small to medium-sized passerine birds (mostly) restricted to the New World. They are typically dull-plumaged and greenish in color the smaller species resembling wood warblers apart from their heavier bills.