[ 'sɪləˌdʒɪz(ə)m ]
■ noun a form of reasoning in which a conclusion is drawn from two given or assumed propositions (premises); a common or middle term is present in the two premises but not in the conclusion, which may be invalid (e.g. all dogs are animals; all animals have four legs; therefore all dogs have four legs ).
Derivatives
syllogistic adjective
syllogistically adverb
syllogize or syllogise verb
Origin
ME: via OFr. or L. from Gk sullogismos , from sullogizesthai , from sun- 'with' + logizesthai 'to reason' (from logos 'reasoning').