Where does “Soufrière” come from?

Soufrière (English) comes from French soufrière, from French soufre, from Old French sulfre, from Latin sulfur, from Proto-Indo-European swelplos, from Proto-Indo-European swel- — to smolder; burn; scorch; beam, board, frame,...

Ancestry of “Soufrière”, step by step

Step	Language	Word	Meaning
1	French	soufrière	sulfur mine; solfatara
2	French	soufre	sulfur
3	Old French	sulfre	sulphur
4	Latin	sulfur	sulfur, brimstone; lightning
5	Proto-Indo-European	swelplos	—
6	Proto-Indo-European	swel-	to smolder; burn; scorch; beam, board, frame,...

Every word from Proto-Indo-European swel- →Every word from Proto-Indo-European swelplos →Every word from Latin sulfur →