Cognate: 141 hairetikós (an adjective, derived from 138 /hairéomai, "to choose, have a distinctive opinion") – a factious person, specializing in half-truths and misimpressions "to win others over" to their personal opinion (misguided zeal) – while creating harmful divisions (used only in Tit 3:10). See 139 (hairesis).

αἱρετικός, (ή, (see αἱρέω);

1. fitted or able to take or choose a thing; rare in secular authors.

2. schismatic, factious, a follower of false doctrine: Titus 3:10.

From the same as hairetizo; a schismatic -- heretic (the Greek word itself).

see GREEK hairetizo