The Collaborative International Dictionary of English v.0.48:

Avow \A*vow"\, v. t. [imp. & p. p. Avowed (?); p. pr. & vb. n.
   Avowing.] [F. avouver, fr. L. advocare to call to (whence
   the meanings, to call upon as superior; recognize as lord,
   own, confess); ad + vocare to call. See Advocate,
   Avouch.]
   1. To declare openly, as something believed to be right; to
      own or acknowledge frankly; as, a man avows his principles
      or his crimes.
      [1913 Webster]

            Which I to be the of Israel's God
            Avow, and challenge Dagon to the test. --Milton.
      [1913 Webster]

   2. (Law) To acknowledge and justify, as an act done. See
      Avowry. --Blackstone.
      [1913 Webster]

   Syn: To acknowledge; own; confess. See Confess.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Avowed \A*vowed"\, a.
   Openly acknowledged or declared; admitted. -- A*vow"ed*ly,
   adv.
   [1913 Webster]

WordNet (r) 3.0 (2006):

avowed
    adj 1: openly declared as such; "an avowed enemy"; "her
           professed love of everything about that country";
           "McKinley was assassinated by a professed anarchist"
           [syn: avowed(a), professed(a)]

Moby Thesaurus II by Grady Ward, 1.0:

55 Moby Thesaurus words for "avowed":
   accepted, acknowledged, admitted, affirmed, alleged, allowed,
   announced, approved, asserted, asseverated, attested,
   authenticated, averred, avouched, certified, claimed, conceded,
   confessed, confirmed, countersigned, declared, deposed, endorsed,
   enunciated, granted, hypocritical, in name only, manifestoed,
   notarized, ostensible, pledged, predicated, pretended, pretexted,
   professed, pronounced, purported, ratified, received, recognized,
   sealed, signed, so-called, specious, stamped, stated, sworn,
   sworn and affirmed, sworn to, underwritten, validated, vouched,
   vouched for, vowed, warranted