ἄχυρον

Etymology
According to Beekes: from and related to  (particularly, identical to the form ) and to. Note the Pre-Greek suffix, similar to that in the synonym. The traditional connection to, 🇨🇬, etc., from , must be rejected.

Noun

 * 1)  chaff, bran, husks left after threshing or grinding
 * 2)  slag from gold smelting
 * 1)  slag from gold smelting