Where does “pustule” come from?

pustule (Middle English) comes from Old French pustule, from Latin pustula, from Finnish pus-, from Proto-Indo-European bew- — "low-pitch humming noise".

Ancestry of “pustule”, step by step

StepLanguageWordMeaning
1Old Frenchpustulepustule
2Latinpustulainflamed sore, blister, pustule
3Finnishpus-—
4Proto-Indo-Europeanbew-"low-pitch humming noise"

Words derived from “pustule”

Every word from Proto-Indo-European bew- →Every word from Finnish pus- →Every word from Latin pustula →