Strong’s Greek
G2433 — hilaskomai
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
ἱλάσκομαι
hilaskomai — pronounced hil-as'-kom-ahee
middle voice from the same as 2436; to conciliate, i.e. (transitively) to atone for (sin), or (intransitively) be propitious:--be merciful, make reconciliation for. see GREEK for 2436
2 occurrences in the KJV.
Luke 18:13
And the publican, standing afar off, would not lift up so much as his eyes unto heaven, but smote upon his breast, saying, God be merciful to me a sinner.
Hebrews 2:17
Wherefore in all things it behoved him to be made like unto his brethren, that he might be a merciful and faithful high priest in things pertaining to God, to make reconciliation for the sins of the people.