The Collaborative International Dictionary of English v.0.48:

Self-denying \Self`-de*ny"ing\, a.
   Refusing to gratify one's self; self-sacrificing. --
   Self`-de*ny"ing*ly, adv.
   [1913 Webster]

WordNet (r) 3.0 (2006):

self-denying
    adj 1: willing to deprive yourself [syn: self-denying, self-
           giving, self-sacrificing]
    2: used especially of behavior [syn: renunciant,
       renunciative, self-abnegating, self-denying]