Where does “bollen” come from?

bollen (Middle English) comes from Old Norse bólgna, from Old Norse bólginn, from Proto-Germanic belganą, from Proto-Indo-European bʰelǵʰ-, from Proto-Indo-European bʰel-, from Proto-Indo-European bʰōl-.

Ancestry of “bollen”, step by step

StepLanguageWordMeaning
1Old Norsebólgnato swell, become swollen
2Old Norsebólginnswollen
3Proto-Germanicbelganąto swell
4Proto-Indo-Europeanbʰelǵʰ-to swell
5Proto-Indo-Europeanbʰel-to sound; to speak, roar, bark; shiny, white; to...
6Proto-Indo-Europeanbʰōl-—
Every word from Proto-Indo-European bʰōl- →Every word from Proto-Indo-European bʰel- →Every word from Proto-Indo-European bʰelǵʰ- →