• Webster's Revised Unabridged Dictionary
    • n Thorntail (Zoöl) A beautiful South American humming bird (Gouldia Popelairii), having the six outer tail feathers long, slender, and pointed. The head is ornamented with a long, pointed crest.
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Century Dictionary and Cyclopedia
    • n thorntail A humming-bird of the genus Gouldia, having long sharp tail-feathers (whence the genus is also called Prymnacantha). The one with the most spine-like rectrices is G. popelairei, 4½ inches long, the male of a shining grass-green color, varied in some places with red, steel-blue, black, and white. It inhabits the United States of Colombia, Ecuador, and Peru.
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