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

senescent \senes"cent\, a. l. senescent, p. pr. of senescere
   to grow old, incho. fr. senere to be old.
   growing old; decaying with the lapse of time. "the night was
   senescent." --poe. "with too senescent air." --lowell.
   1913 webster

[2] : WordNet (r) 2.0

senescent
     adj : growing old syn: aging, ageing
see also:
aging ageing 

Senescent >> S Words
Senescent, definition of term: Senescent
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