Webster's Revised Unabridged Dictionary · 1913

Vireo

Vireo , noun

[Latin, a species of bird.]

(Zoology) Any one of numerous species of American singing birds belonging to Vireo and allied genera of the family Vireonidae. In many of the species the back is greenish, or olive-colored. Called also greenlet.

In the Eastern United States the most common species are the white-eyed vireo (Vireo Noveboracensis), the red-eyed vireo (Vireo olivaceus), the blue-headed, or solitary, vireo (Vireo solitarius), the warbling vireo (Vireo gilvus), and the yellow-throated vireo (Vireo flavifrons). All these are noted for the sweetness of their songs.