bourdon
/ˈbʊədən/noun
- Music a low-pitched stop in an organ or harmonium, typically a stopped diapason 16-foot pitch【乐】布尔东低音; 管风琴（或风琴）的低音音栓（尤指16音阶音高的主音栓）。
词源
Middle English （in the sense 'drone of a bagpipe'）： from Old French, 'drone', of imitative origin.