- a bluish-green and white swallow, Iridoprocne bicolor, of North America, that nests in tree cavities.
Origin of tree swallow
An Americanism dating back to 1890–95
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for tree swallow
The peasants call it tree-swallow, but its name is something else.In Midsummer Days and Other Tales