Definition of deer fly in English:

deer fly

noun

  • 1A bloodsucking louse fly which is a parasite of deer. It loses its wings on finding a host, and the female gives birth to fully grown larvae.

    • ‘Swatting at mosquitoes and deer flies, the five picked their way through the Florida scrub, trying to avoid the briars and sawgrass sharp as a sword blade.’
    • ‘The mosquitoes and horse and deer flies were out in force and bent on extracting blood and flesh.’
    • ‘For years I had a terrible problem with face flies, deer flies and ticks.’
    • ‘Minutes after I began my walk, deer flies buzzed around my ears and two mosquitoes lodged in my left eye.’
  • 2A bloodsucking horsefly which attacks humans and other large mammals. It can transmit various diseases, including tularaemia.

    • ‘Having the rabbit as my companion, albeit for only a short while, was a welcome distraction from the black deer flies attracted by my sweat.’
    • ‘Biting flies common in the U.S. include the species Chrysops discalis (deer fly), Chrysops aestuans, Chrysops relictus, and Chrysozona pluvialis.’