LSJ
ὁ, worship of heroes, IG 12(2).29 (Mytil., spelt ἡρωοισμός); — hence ἡρωοισταί, οἱ, IG2². 1339 (i BC); ἡρωεισταί Annuario 4/5.482; ἡρωϊασταί BCH 50.15 (Delph., iv BC), 2². 255 (Acraephia); later ἡρῳστής.
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)