FROM STRONG’S GREEK DICTIONARY (1890)

Strong’s Greek Dictionary (1890) — public domain, printed whole.

hilasterion ἱλαστήριον — hil-as-tay'-ree-on — neuter of a derivative of 2433; an expiatory (place or thing), i.e. (concretely) an atoning victim, or (specially) the lid of the Ark (in the Temple):--mercyseat, propitiation.

see GREEK for 2433