A gadfly is an irritating person, a nuisance who will often ask too many questions or lob lots of criticisms in order to get his or her way.

Gadfly can also refer to an actual fly. The next time you see a cow swatting at the air with her tail, look closer because she might actually be shooing away an annoying gadfly. This is any kind of fly that likes to pester, and even bite, livestock. The prefix gad is an old word for “spike” or “pointed stick” which can be thought of, in this case, as similar to a stinger. So if your office mate is continuously buzzing around your desk with stinging comments, call him a gadfly and try to shoo him back to his own desk.

Definitions of gadfly
  1. noun
    any of various large flies that annoy livestock
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    stout-bodied hairy dipterous fly whose larvae are parasites on humans and other mammals
    warble fly
    hairy bee-like fly whose larvae produce lumpy abscesses (warbles) under the skin of cattle
    cleg, clegg, horse fly, horsefly
    large swift fly the female of which sucks blood of various animals
    Gasterophilus intestinalis, horse botfly
    parasitic chiefly on horses
    Dermatobia hominis, human botfly
    large tropical American fly; parasitic on humans and other mammals
    Oestrus ovis, sheep botfly, sheep gadfly
    larvae are parasitic on sheep
    type of:
    two-winged insects characterized by active flight
  2. noun
    a persistently annoying person
    synonyms: blighter, cuss, pest, pesterer
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    nudnick, nudnik
    (Yiddish) someone who is a boring pest
    type of:
    persecutor, tormenter, tormentor
    someone who torments
Word Family

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