Where does “嗅覚器官” come from?

嗅覚器官 (Japanese) comes from Japanese 嗅覚 — sense of smell.

嗅覚器官 (Japanese): olfactory organ

Definitions

Step	Language	Word	Meaning
1	Japanese	嗅覚	sense of smell

嗅覚器官 — Etymology, Origin & Word History | Etymology Explorer