Abbott-Smith Manual Greek Lexicon
ἐπι-σύστασις (G1999)
7 † ἐπι-σύστασις , -εως, ἡ ( ἐπισυνίστημι ) [in LXX: Nu 16:40 ( עֵדָה ) 26:9 ( נָצָה hi.), I Es 5:73 A* ;] a gathering, a riotous throng : Rec. (for ἐπίστασις , q.v.), Ac 24:12 , II Co 11:28 .†
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain