MEANING: noun:
1. Any of the various types of flies that bite or annoy livestock.
2. One who persistently annoys.

ETYMOLOGY: From gad (a goad for cattle), from Middle English, from Old Norse gaddr. Earliest documented use: 1626.

GLADFLY - one that has avoided a spider's web at the last minute

GAFFLY - how you behave after encountering a violent fisherman with a long barbed spear

WADFLY - what happens to a mis-aimed chaw of tobacco