REDUNDANT

adj. abundant, plentiful; excessive, superfluous; unnecessarily repetitive; serving as a duplicate back-up system for use in the event of failure of the primary system; unemployed, laid-off

Redundancy, in general terms, refers to the quality or state of being redundant, that is: exceeding what is necessary or normal; or duplication. This can have a negative connotation, especially in rhetoric: superfluous or repetitive; or a positive implication, especially in engineering: serving as a duplicate for preventing failure of an entire system.
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Redundancy Medtalk The duplication of time-sensitive or failure-prone equipment–eg, computer server, surgical supplies, etc–allowing the [more]Redundant - Community and Resources

Adjective
1. more than is needed, desired, or required; "trying to lose excess weight"; "found some extra change lying on the dresser"; "yet another book on heraldry might be thought redundant"; "skills made redundant by technological advance"; "sleeping in the spare room"; "supernumerary ornamentation"; "it was supererogatory of her to gloat"; "delete superfluous (or unnecessary) words"; "extra ribs as well as other supernumerary internal parts"; "surplus cheese distributed to the needy"
(synonym) excess, extra, spare, supererogatory, superfluous, supernumerary, surplus
(similar) unnecessary, unneeded
2. use of more words than required to express an idea; "a wordy gossipy account of a simple incident"; "a redundant text crammed with amplifications of the obvious"
(synonym) wordy
(similar) prolix
3. repetition of same sense in different words; "`a true fact' and `a free gift' are pleonastic expressions"; "the phrase `a beginner who has just started' is tautological"; "at the risk of being redundant I return to my original proposition"- J.B.Conant
(synonym) pleonastic, tautologic, tautological
(similar) prolix

(a.)
Using more worrds or images than are necessary or useful; pleonastic.
  

(a.)
Exceeding what is natural or necessary; superabundant; exuberant; as, a redundant quantity of bile or food.