[1] : The Collaborative International Dictionary of English v.0.48

obsolesce \ob`solesce"\, v. i. l. obsolescere. see
   obsolescent.
   to become obsolescent. r. --fitzed. hall.
   1913 webster
see also:
obsolescent 

[2] : WordNet (r) 2.0

obsolesce
     v : become obsolete, fall into disuse; "this word has not
         obsolesced, although it is rarely used"

[3] : Moby Thesaurus II by Grady Ward, 1.0

20 moby thesaurus words for "obsolesce":
   age, antiquate, be superseded, become extinct, become obsolete,
   date, fade, fall into disuse, fossilize, fust, go out, grow old,
   lose currency, molder, obsolete, outdate, pass away, perish, rust,
   superannuate

Obsolesce >> O Words
Obsolesce, definition of term: Obsolesce
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