French soufre

← Old French sulfre (inherited)

← Old French soffre (mention)

← Proto-Indo-European *swelplos (inherited)

← Proto-Indo-European *swel- (mention)

← Latin sulfur (inherited)

← Latin sulphur (mention)

→ Catalan sofre (cognate)

→ French soufrer (suffix)

→ French sulfureux (mention)

→ French octasoufre (prefix)

→ French soufrière (suffix)

→ Ido sulfo (borrowed)