Strong’s Greek
G440 — anthrax
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
ἄνθραξ
anthrax — pronounced anth'-rax
of uncertain derivation; a live coal:--coal of fire.
1 occurrence in the KJV.
Romans 12:20
Therefore if thine enemy hunger, feed him; if he thirst, give him drink: for in so doing thou shalt heap coals of fire on his head.