1. Large swift fly the female of which sucks blood of various animals
   "horseflies, also known as horse flies, can deliver painful bites";
   - cleg [Brit], clegg [Brit, rare], horse fly
    
2. Winged fly parasitic on horses
   "The horses grew restless as horseflies buzzed around them";
   - Hippobosca equina

Derived forms: horseflies

Type of: gadfly, hippoboscid, louse fly

Part of: family Tabanidae, genus Hippobosca, Hippobosca, Tabanidae

Encyclopedia: Horsefly, British Columbia