It is defined as a deductive argument that is invalid. The argument could have true premises, but still have a false conclusion.
ɪ t WORD_BOUNDARY ɪ z WORD_BOUNDARY d ɪ f aɪ n d WORD_BOUNDARY æ z WORD_BOUNDARY ʌ WORD_BOUNDARY d ɪ d ʌ k t ɪ v WORD_BOUNDARY ɑ ɹ ɡ j uː m ə n t WORD_BOUNDARY ð æ t WORD_BOUNDARY ɪ z WORD_BOUNDARY ɪ n v æ l ɪ d WORD_BOUNDARY ð ɪ WORD_BOUNDARY ɑ ɹ ɡ j uː m ə n t WORD_BOUNDARY k ʊ d ʌ v WORD_BOUNDARY t ɹ uː WORD_BOUNDARY p ɹ ɛ m ɪ s ɪ z WORD_BOUNDARY b ʌ t WORD_BOUNDARY s t ɪ l WORD_BOUNDARY h æ v WORD_BOUNDARY ʌ WORD_BOUNDARY f ɔ l s WORD_BOUNDARY k ə ŋ k l uː ʒ ə n WORD_BOUNDARY