Source : Webster's Revised Unabridged Dictionary (1913)

Myriad \Myr"i*ad\, a.
   Consisting of a very great, but indefinite, number; as,
   myriad stars.

Myriad \Myr"i*ad\, n. [Gr. ?, ?, fr. ? numberless, pl. ? ten
   thousand: cf. F. myriade.]
   1. The number of ten thousand; ten thousand persons or
      things.

   2. An immense number; a very great many; an indefinitely
      large number.

Source : WordNet®

myriad
     adj : 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}, {myriad(a)}, {multitudinous},
            {numberless}, {uncounted}, {unnumberable}, {unnumbered},
            {unnumerable}]
     n 1: a large indefinite number; "he faced a myriad of details"
     2: the cardinal number that is the product of ten and one
        thousand [syn: {ten thousand}, {10000}]