different between gadder vs hadder

English

gad +? -er

gadder (plural gadders)

One who roves about idly, a rambling gossip.
- 1662, Thomas Fuller, History of the Worthies of England
  He was no gadder abroad, or discontinuer from his convent, for a long time.
(obsolete) A drilling or perforating machine or apparatus for mining and mineral exploration.

From Middle English hader, hather, heddre, from Old English *h?ddre, a variant of h?þ (“heath; heather”). More at heath, heather.

hadder (countable and uncountable, plural hadders)

hadder

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