See also horse fly.
- any of a number of large dipterous flies (family Tabanidae), the female of which sucks the blood of horses, cattle, etc.
- any of various other dipterous flies that bite or infest horses, esp. any of a family (Gasterophilidae) of botflies
Origin of horseflyMiddle English hors fleege
also horse fly
Any of numerous large biting tabanid flies, the females of which feed on the blood of various mammals.