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

octogenarian \oc`togena"rian\, n.
   a person eighty years, or more, of age.
   1913 webster

[2] : WordNet (r) 2.0

octogenarian
     adj : being from 80 to 89 years old
     n : someone whose age is in the eighties

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

84 moby thesaurus words for "octogenarian":
   father time, l, methuselah, nestor, old paar, sexagesima, boxcar,
   boxcars, centenarian, dotard, dozen, duodecimo, eighty, elder,
   eleven, fifteen, fifty, five and twenty, fortnight, forty,
   four and twenty, fourscore, fourscore and ten, fourteen, gaffer,
   geezer, golden-ager, gramps, grandfather, grandsire, graybeard,
   half a hundred, long dozen, ninety, nonagenarian, old chap,
   old codger, old dog, old duffer, old geezer, old gent,
   old gentleman, old man, old party, old-timer, older, oldster,
   pantaloon, patriarch, presbyter, quindecennial, quindecim,
   quindecima, quindene, score, senior citizen, septuagenarian,
   seventy, sexagenarian, sexagenary, sexagesimo-quarto, sixteen,
   sixteenmo, sixty, sixty-four, sixty-fourmo, teens,
   the quiet-voiced elders, thirteen, thirty-two, thirty-twomo,
   threescore, threescore and ten, twelve, twelvemo, twenty,
   twenty-five, twenty-four, twenty-fourmo, two dozen, two weeks,
   twoscore, venerable sir, veteran

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