αἱρετ-ιστής · hairet-istēs — LSJ
one who chooses, τινός Plb. 22.6.11.
partisan, τῶν τρόπων τινός Philem. 131, cf. Plb. 1.79.9, etc.; founder of a philosophical school, D.L. 9.6; τῶν λόγων Vit.Philonid. p.12 C.
sectarian, J. BJ 2.8.2, Iamb. Protr. 21.κά.
Astrol., belonging to the ‘condition’, Jul.Laod. in Cat.Cod.Astr. 5(1).183.