αἱρεσιάρχης
From LSJ
Διάλυε, μὴ σύγκρουε μαχομένους φίλους → Iurgia amicorum solvas, haud intenderis → Den Streit von Freunden schlichte, fache ihn nicht an
English (LSJ)
ου, ὁ,
A leader of a school, S.E.P.3.245; esp. of a medical school, IG14.1759, Gal.6.372; heresiarch, Just.Nov. 42.1.1 (pl.). II Astrol., dominating the 'condition' (cf. αἵρεσις B. 11.4), Paul.Al.R.3.