A repetition of the same meaning in different words; needless repetition of an idea in different words or phrases; a representation of anything as the cause, condition, or consequence of itself, as in the following lines: --The dawn is overcast, the morning lowers,And heavily in clouds brings on the day. Addison.
the repetitious or unnecessary use of words that do not provide new information in an utterance, as Hear, hear! or I myself said... Note: Tautologies occur commonly in everyday speech. adj. tautologous.
the saying of the same thing twice over in different words a statement in which the predicate asserts no more than is contained in the meaning of the subject an instance of a valid formula of propositional logic a complex proposition which is true independently of the truth values of its constituent atomic propositions a statement that is necessarily true an analytic statement see also: propositional tautology