Emily Dickinson Lexicon

PLE'O-NASM, n. [L. pleonasmus; Gr. πλεονασμος, from the root of πλεος, full, πλειον, more, L. pleo, in impleo, to fill.]

Redundancy of words in speaking or writing; the use of more words to express ideas, than are necessary. This may be justifiable when we intend to present thoughts with particular perspicuity or force.