Source : Webster's Revised Unabridged Dictionary (1913)

Claimant \Claim"ant\, n. [Cf. OF. clamant, p. pr. of clamer. Cf.
   {Clamant}.]
   One who claims; one who asserts a right or title; a claimer.

Source : WordNet®

claimant
     n : someone who claims a benefit or right or title; "claimants
         of unemployment compensation"; "he was a claimant to the
         throne"