Where does “каучук” come from?

каучук (Russian) comes from French caoutchouc, from Spanish caucho, from Quechua kawchu.

Ancestry of “каучук”, step by step

Step	Language	Word	Meaning
1	French	caoutchouc	rubber
2	Spanish	caucho	rubber
3	Quechua	kawchu	—

каучук — Etymology, Origin & Word History | Etymology Explorer