Lewis & Short

immĕrens (inm-), entis (in tmesi: inque merentes, Lucr. 2, 1104), adj. [inmereo], undeserving, not meriting, innocent (poet. and in post-Aug. prose; cf. indignus): triste lignum, caducum In domini caput immerentis, Hor. C. 2, 13, 11; id. Epod. 6, 1; 7, 19; Suet. Tit. 10: quaedam immerentia, innocent, harmless things, Val. Max. 9, 12, 8: inscitum efferre injuriam tibi immerenti, Ter. Hec. 5, 1, 14.
Subst.: im-mĕrens, entis, m., one who is innocent, does not deserve any thing: male mereri de inmerenti inscitiast, Plaut. Curc. 1, 3, 29.
Adv.: immĕrenter (inm-), undeservedly: a Philippo rege temulento immerenter damnata, Val. Max. 6, 2, ext. 1.