: any of various stout dipteran flies of the family Oestridae that have larvae parasitic in cavities or tissues of various mammals including humans
Any member of several dipteran families with beelike adults and larvae that are parasitic on mammals. Some species are serious pests of horses, cattle, deer, sheep, rabbits, and squirrels, and one species (the human botfly) attacks humans. Adults of several species lay many eggs (nits) on the host's body, and the emerging larvae penetrate its skin. The larvae reemerge through the skin, then mature into egg-laying adults. In the New World tropics, the botfly's infestation of cattle has led to loss of beef and hides. See alsowarble fly.