tautology (n.)

1570s, from Late Latin tautologia "representation of the same thing in other words," from Greek tautologia, from tautologos "repeating what has been said," from tauto "the same" (contraction of to auto, with to "the" + auto, see auto-) + -logos "saying," related to legein "to say," from PIE root *leg- (1) "to collect, gather," with derivatives meaning "to speak (to 'pick out words')." Related: Tautological.