1. 
[syn: countless, infinite, innumerable, innumerous, multitudinous, myriad, numberless, uncounted, unnumberable, unnumbered, unnumerable]
The Collaborative International Dictionary of English v.0.48:
Numberless \Num"ber*less\, a.
   Innumerable; countless.
   [1913 Webster]
WordNet (r) 3.0 (2006):
numberless
    adj 1: too numerous to be counted; "incalculable riches";
           "countless hours"; "an infinite number of reasons";
           "innumerable difficulties"; "the multitudinous seas";
           "myriad stars"; "untold thousands" [syn: countless,
           infinite, innumerable, innumerous, multitudinous,
           myriad, numberless, uncounted, unnumberable,
           unnumbered, unnumerable]
Moby Thesaurus II by Grady Ward, 1.0:
18 Moby Thesaurus words for "numberless":
   countless, endless, immeasurable, incalculable, inexhaustible,
   infinite, innumerable, measureless, myriad, no end of, numerous,
   uncountable, uncounted, unmeasured, unnumbered, untold,
   without end, without limit