noun, feminine/bɔ̃.bɔn/plural: bonbonnes
demijohn, carboy; gas cylinder
“Une bonbonne de gaz.”
From Occitan boumbouno m [from boumbo + -ouno, ultimately from Latin bombus and -ōnem], made feminine under the influence of French bonne (unrelated), and with change of bomb- to bonb- under the influence of French bonbon (also unrelated). By surface analysis, bombe + -on. Although less common, the spelling bombonne more accurately reflects the Latin bomb- root.