κοινωνός, -ή, -όν (< κοινός), [in LXX: Refs Pro.28:24, Isa.1:23 (חָבֵר), Mal.2:14 (חֲבֶרֶת), Est.8:13, al. ;] __1. as adj., = κοινός. __2. As subst., ὁ, ἡ κ., __(a) a partner, associate, companion: Refs 2Co.8:23, Phm 17; with dative of person(s), Luk.5:10; with genitive of person(s), Heb.10:33; id. before ἐν, Mat.23:30; __(b) a partaker, sharer: with genitive of thing(s), Refs 1Co.10:18 10:20, 2Co.1:7, 1Pe.5:1, 2Pe.1:4 (see Deiss., BS, 368 n2).† (AS)
1) a partner, associate, comrade, companion 2) a partner, sharer, in anything 2a) of the altar in Jerusalem on which the sacrifices are offered 2a1) sharing in the worship of the Jews 2b) partakers of (or with) demons 2b1) brought into fellowship with them, because they are the authors of heathen worship
From G2839; a sharer, that is, associate
KJV Usage: companion, X fellowship, partaker, partner.