The Collaborative International Dictionary of English v.0.48:

acknowledged \ac*knowl"edged\ ([a^]k*n[o^]l"[e^]jd) adj.
   Generally accepted or recognized as correct or reasonable.
   Opposite of unacknowledged. [Narrower terms: given,
   granted; unquestionable (vs. questionable)] Also See:
   known.

   Syn: accepted, recognized
        [WordNet 1.5 +PJC]