not your usual insect!

A gadfly is not ONLY an irritating pest hovering around your poor horse! Sure, it’s a noun: a fly that bites livestock, especially a horsefly, warble fly, or botfly. But its other meaning is: an annoying person, especially one who provokes others into action by criticism.

 

 

Hailing from the late 16th century: from gad, or obsolete gad ‘goad, spike,’ from Old Norse gaddr, of Germanic origin.