(Science: study) 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)
Tautology, repetition. There may be frequent repetitions (as in legal instruments) which are warranted either by necessity or convenience; but tautology is always a fault, being a sameness of expression which adds nothing to the sense or the sound.
Origin: L. Tautologia, Gr., cf. F. Tautologie.