The Collaborative International Dictionary of English v.0.48:

morals \morals\ n.
   motivation based on ideas of right and wrong.

   Syn: ethical motive, ethics, morality.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

morals
    n 1: motivation based on ideas of right and wrong [syn: ethical
         motive, ethics, morals, morality]

Moby Thesaurus II by Grady Ward, 1.0:

34 Moby Thesaurus words for "morals":
   Ten Commandments, Zeitgeist, axiology, behavioral norm,
   business ethics, code, code of ethics, code of morals, conduct,
   decalogue, ethic, ethical system, ethicality, ethicalness, ethics,
   ethos, habits, legal ethics, medical ethics, moral climate,
   moral code, moral principles, morale, morality, mores,
   new morality, norm, normative system, principles,
   professional ethics, social ethics, standards, value system,
   virtue