The Collaborative International Dictionary of English v.0.48:

Avowal \A*vow"al\, n.
   An open declaration; frank acknowledgment; as, an avowal of
   such principles. --Hume.
   [1913 Webster]

WordNet (r) 3.0 (2006):

avowal
    n 1: a statement asserting the existence or the truth of
         something [syn: avowal, avouchment, affirmation]