Vehemence, or violence, in altercation or disputation or litigation; (S, K;) and ability, or power, to practise it: (K:) [or simply contention in an altercation; disputation; or litigation:] a subst. from جَادَلَهُ: (S:) or verbal noun of جَدِلَ [q. v.]. (Msb.)
2.
Hence, as a term of logic, A syllogism composed of things well known, or conceded; the object of which is to convince the opponent, and to make him to understand who fails to apprehend the premises of the demonstration. (TA.)