propagator
/ˈprɒpəgeɪtə(r)/noun
1
- a covered, typically electrically heated, container filled with earth or compost, used for germinating or raising seedlings种子发生罐（尤指用电加热、内装土壤或肥料、用来使幼苗发芽或发育的有盖容器）。
2
- a person who spreads and promotes an idea, theory, or branch of knowledge（观点、理论或知识的）传播者, 宣传者：
a propagator of the doctrine.
该信条的传播者。