Horsefly \Horse"fly`\, n.; pl. {Horseflies}.
1. (Zo["o]l.) Any dipterous fly of the family {Tabanid[ae]},
that stings horses, and sucks their blood.
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}.
2. (Zo["o]l.) The horse tick or forest fly ({Hippobosca}).