Where does “drone-a-thon” come from?

drone-a-thon (English) comes from English drone, from Middle English drounen — to roar, bellow.

Ancestry of “drone-a-thon”, step by step

drone-a-thon traces back through two separate lines of ancestry.

via English drone

StepLanguageWordMeaning
1EnglishdroneA male ant, bee or wasp, which does not work but...
2Middle Englishdrounento roar, bellow

via English a-thon

StepLanguageWordMeaning
1Englisha-thon
Every word from Middle English drounen