Horsefly \Horse"fly`\, n.; pl. {Horseflies}.
1. (Zool.) Any dipterous fly of the family {Tabanid[ae]},
that stings horses, and sucks their blood.
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Note: Of these flies there are numerous species, both in
Europe and America. They have a large proboscis with
four sharp lancets for piercing the skin. Called also
{breeze fly}. See Illust. under {Diptera}, and {Breeze
fly}.
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2. (Zool.) The horse tick or forest fly ({Hippobosca}).
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