ἱλαςμός

A. a means of appeasing, in pl., Plu. Sol. 12, Orph. A. 39,554,etc.
2. atonement, sinoffering, LXX Ez. 44.27, 2 Ma. 3.33, 1 Ep.Jo. 2.2,4.10, Ph. 1.121.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
An open-access project