• WordNet 3.6
    • n gallfly any of various insects that deposit their eggs in plants causing galls in which the larvae feed
    • n gallfly fragile mosquito-like flies that produce galls on plants
    • n gallfly small solitary wasp that produces galls on oaks and other plants
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Webster's Revised Unabridged Dictionary
    • n Gallfly (Zoöl) An insect that deposits its eggs in plants, and occasions galls, esp. any small hymenopteran of the genus Cynips and allied genera. See Illust. of Gall.
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Century Dictionary and Cyclopedia
    • n gallfly An insect which occasions galls on plants by puncturing them; especially, a hymenopter of the group Gallicolæ or Diplolepariæ, as a cynipid. See gall, and cut under Cynips.
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Chambers's Twentieth Century Dictionary
    • Gallfly an insect which occasions gall on plants by puncturing
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Chambers's Twentieth Century Dictionary
Fr. galle—L. galla, oak-apple.


In literature:

This domestic arrangement calls to mind the curious family of gallflies.
"My First Summer in the Sierra" by John Muir
To this order belong the gallflies, the sawflies, the ichneumons, and, above all, the ants and bees.
"On the Origin and Metamorphoses of Insects" by Sir John Lubbock