from
The Collaborative International Dictionary of English v.0.48
Gadfly \Gad"fly`\ (g[a^]d"fl[imac]`), n.; pl. {Gadflies}. [Gad +
fly.] (Zool.)
Any dipterous insect of the genus {Oestrus}, and allied
genera of botflies.
[1913 Webster]
Note: The sheep gadfly ({Oestrus ovis}) deposits its young in
the nostrils of sheep, and the larv[ae] develop in the
frontal sinuses. The common species which infests
cattle ({Hypoderma bovis}) deposits its eggs upon or in
the skin where the larv[ae] 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}.
[1913 Webster]
{Gadfly petrel} (Zool.), one of several small petrels of the
genus {Oestrelata}.
[1913 Webster]