Extended Strong's Greek Lexicon (Abbott-Smith based)
persuasive speech
Usage: πιθανολογία, -ας, ἡ (πιθανός, persuasive, plausible), in cl. (Plat), the use of probable arguments, as opposite to demonstration (ἀπόδειξις); hence, persuasive speech: Col.2:4 (see ICC, in l).† (AS)