Strong’s Greek
G1518 — eirenopoios
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
εἰρηνοποιός
eirenopoios — pronounced i-ray-nop-oy-os'
from 1518 and 4160; pacificatory, i.e. (subjectively) peaceable:--peacemaker. see GREEK for 1518 see GREEK for 4160
1 occurrence in the KJV.
Matthew 5:9
Blessed are the peacemakers: for they shall be called the children of God.