• WordNet 3.6
    • n gadfly any of various large flies that annoy livestock
    • n gadfly a persistently annoying person
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Webster's Revised Unabridged Dictionary
    • n Gadfly găd"flī` (Zoöl) Any dipterous insect of the genus Oestrus, and allied genera of botflies.☞ The sheep gadfly Oestrus ovis) deposits its young in the nostrils of sheep, and the larvæ develop in the frontal sinuses. The common species which infests cattle (Hypoderma bovis) deposits its eggs upon or in the skin where the larvæ or bots live and produce sores called wormels. The gadflies of the horse produce the intestinal parasites called bots. See Botfly, and Bots. The true horseflies are often erroneously called gadflies, and the true gadflies are sometimes incorrectly called breeze flies.
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Century Dictionary and Cyclopedia
    • n gadfly The popular name of sundry flies which goad or sting domestic animals, as a breeze, breeze-fly, or horse-fly; specifically, a dipterous insect of the family Tabanidæ and suborder Brachycera, representing also a superfamily Hexachætæ. They are comparatively large, very active, voracious, and bloodthirsty, with great powers of biting, the mouth-parts being more highly developed than those of any other dipterous insect. They have also great power of flight. The bite is deep and painful, often drawing blood, though not poisonous. In strictness, only the females are gadflies, the males being smaller and quite inoffensive, living on juices of plants. There are more than 1,000 species, of the genera Tabanus, Chrysops, Hæmatopota, and others. One of the commonest gadflies which attack cattle and horses is Tabanus bovinus. See also out under Chrysops.
    • n gadfly A common though erroneous name of sundry flies (bot-flies) of the family Œstridæ and genus Œstrus or Hippoderma, belonging to a different series of the great order Diptera from that of gadflies proper. These flies sting animals with their ovipositor, and deposit their eggs in the skin.
    • n gadfly Figuratively, one who is constantly going about; a mischievous or annoying gadabout.
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Chambers's Twentieth Century Dictionary
    • n Gadfly gad′flī a fly which pierces the skin of cattle in order to deposit its eggs: a mischievous gadabout.
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Webster's Revised Unabridged Dictionary
Gad, + fly,
Chambers's Twentieth Century Dictionary
From gad, n., fly.


In literature:

The weather had for a considerable time been hot and dry, and mosquitoes and gadflies were very troublesome.
"Over the Rocky Mountains" by R.M. Ballantyne
Vigil was becoming uneasy, and a belated gadfly was making continued attacks upon her sensitive skin.
"Teddy: Her Book" by Anna Chapin Ray
In to the forge flew a gadfly.
"The Children of Odin" by Padraic Colum
Go to the gadfly; consider her ways and be wise.
"How to Cook Husbands" by Elizabeth Strong Worthington
Will you hurry now, Gadfly, or is the sun to sink before we get hounds in leash?
"The Strange Adventures of Captain Dangerous, Vol. 1 of 3" by George Augustus Sala
Off went the pirate, like a startled gadfly, to Newfoundland.
"The Corsair King" by Mór Jókai
For since I roamed my fill in other continents the gadfly may no longer sting me out of my tranquil haunts.
"Apologia Diffidentis" by W. Compton Leith
Then in flew Loki again, still disguised as a gadfly, and lighted on Brock's neck and stung him so that the blood flowed.
"Told by the Northmen:" by E. M. [Ethel Mary] Wilmot-Buxton
He was a clever gadfly, that was all.
"A Critic in Pall Mall" by Oscar Wilde
She was nagged incessantly by a gadfly of conscience that buzzed in her ears the counsel to tell the police.
"The Cup of Fury" by Rupert Hughes

In news:

'The Year of the Gadfly ': Young-Adult Fiction for Smart Adults.
Bravo gadfly Andy Cohen brings Watch What Happens Live to SXSW.
As the Grandeau turns, or: JCOPE gadfly no more.
Politics GOP Gadfly Phil Hart Endorses Ron Paul.
Ken Walter, left, receives a " Gadfly Award" from outgoing legislator Ron Hiatt and the government center on December 15.
A climate gadfly 's job.
Senate Gadfly Who Isn't Shy About Buzzing.
You say gadfly , I say role model.
Washam's law: Gadfly in charge.
A Political Gadfly Lampoons the Left via YouTube.
Gadfly buzzes work sites.
The Long, Strange, and Maybe Even Meaningful Career of a Right-Wing Media Gadfly .
Homeless Gadfly Returns, Warming Up Lawsuits.
Cuomo's New Pal Is Anti-Tax Gadfly Who Sank His Dad.
A few years ago, a city hall gadfly in Philadelphia decided to measure the activism of the city council's 17 members.