noun
chaff
CHAF/tʃæf/
The discarded dry husks of threshed grain.
Dry chaff lies beside the solid wheat kernels after threshing.

Etymology
Old English ceaf already named grain husks, the material separated from the kernels during threshing. The modern agricultural sense preserves that meaning; deeper ancestry is uncertain.
In context
taking stuff and I B I pour it from one bucket to another bucket and let the breeze blow the chaff off of the grain so the stuff we don't want here is very light