The Collaborative International Dictionary of English v.0.48:

Recognize \Rec"og*nize\, v. i. (Law)
   To enter an obligation of record before a proper tribunal;
   as, A B recognized in the sum of twenty dollars. [Written
   also recognise.]
   [1913 Webster]

   Note: In legal usage in the United States the second syllable
         is often accented.
         [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Recognize \Rec"og*nize\ (r[e^]k"[o^]g*n[imac]z), v. t. [imp. &
   p. p. Recognized (r[e^]k"[o^]g*n[imac]zd); p. pr. & vb. n.
   Recognizing (r[e^]k"[o^]g*n[imac]`z[i^]ng).] [From
   Recognizance; see Cognition, and cf. Reconnoiter.]
   [Written also recognise.]
   1. To know again; to perceive the identity of, with a person
      or thing previously known; to recover or recall knowledge
      of.
      [1913 Webster]

            Speak, vassal; recognize thy sovereign queen.
                                                  --Harte.
      [1913 Webster]

   2. To avow knowledge of; to allow that one knows; to consent
      to admit, hold, or the like; to admit with a formal
      acknowledgment; as, to recognize an obligation; to
      recognize a consul.
      [1913 Webster]

   3. To acknowledge acquaintance with, as by salutation,
      bowing, or the like.
      [1913 Webster]

   4. To show appreciation of; as, to recognize services by a
      testimonial.
      [1913 Webster]

   5. To review; to reexamine. [Obs.] --South.
      [1913 Webster]

   6. To reconnoiter. [Obs.] --R. Monro.
      [1913 Webster]

   Syn: To acknowledge; avow; confess; own; allow; concede. See
        Acknowledge.
        [1913 Webster]

WordNet (r) 3.0 (2006):

recognize
    v 1: accept (someone) to be what is claimed or accept his power
         and authority; "The Crown Prince was acknowledged as the
         true heir to the throne"; "We do not recognize your gods"
         [syn: acknowledge, recognize, recognise, know]
    2: be fully aware or cognizant of [syn: recognize,
       recognise, realize, realise, agnize, agnise]
    3: detect with the senses; "The fleeing convicts were picked out
       of the darkness by the watchful prison guards"; "I can't make
       out the faces in this photograph" [syn: spot, recognize,
       recognise, distinguish, discern, pick out, make
       out, tell apart]
    4: perceive to be the same [syn: recognize, recognise]
    5: grant credentials to; "The Regents officially recognized the
       new educational institution"; "recognize an academic degree"
       [syn: accredit, recognize, recognise]
    6: express greetings upon meeting someone [syn: greet,
       recognize, recognise]
    7: express obligation, thanks, or gratitude for; "We must
       acknowledge the kindness she showed towards us" [syn:
       acknowledge, recognize, recognise]
    8: exhibit recognition for (an antigen or a substrate)
    9: show approval or appreciation of; "My work is not recognized
       by anybody!"; "The best student was recognized by the Dean"
       [syn: recognize, recognise]

Moby Thesaurus II by Grady Ward, 1.0:

111 Moby Thesaurus words for "recognize":
   accept, acknowledge, admit, agree, agree provisionally, allow,
   appreciate, apprehend, approve, assent grudgingly, avow,
   be acquainted with, be apprised of, be aware of, be cognizant of,
   be conscious of, be conversant with, be informed, behold, bless,
   catch sight of, clap eyes on, cognize, comprehend, concede,
   conceive, conceptualize, confess, credit, descry, detect,
   determinate, diagnose, discern, discover, distinguish, do homage,
   endorse, espy, express general agreement, fathom, finger,
   give credit, give thanks, glimpse, go along with, grant, grasp,
   have, have in sight, have information about, have knowledge of,
   honor, identify, ken, know, know again, lay eyes on, look on,
   look upon, make acknowledgments of, make out, nail, not oppose,
   note, notice, observe, offer thanks, own, peg, perceive, pick out,
   pick up, pinpoint, place, possess, prehend, ratify, realize,
   recall, recall knowledge of, recollect, reidentify, remark,
   remember, render credit, render thanks, respect, return thanks,
   reward, salute, sanction, savvy, see, seize, sense, sight, spot,
   spy, take in, tell, thank, twig, understand, validate, view,
   warrant, witness, wot, wot of, yield