Where does “มอดไม้” come from?

มอดไม้ (Thai) comes from Thai ไม้, from Proto-Tai *mwajꟲ.

มอดไม้ (Thai): illegal logger

Definitions

Step	Language	Word	Meaning
1	Thai	ไม้	wood; stick; log; tree; plant; mark
2	Proto-Tai	*mwajꟲ	—

มอดไม้ — Etymology, Origin & Word History | Etymology Explorer