Words Mean Things

Examples of Propitiation:
Rom 3:25;
1 John 2:2; 4:10;
Heb 2:17

A noun form ἱλαστήριον, is translated “a propitiation” in Romans 3:25 and “the mercy seat” in Hebrews 9:5.
Another noun form ἱλασμός occurs twice (1 John 2:2; 4:10 ) Christ is “the propitiation for our sins.”
A fourth word ἵλεως is found in Matthew 16:22 Peter: “Be it far from thee, Lord,” and Hebrews 8:12 translated “merciful.”