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.
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   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.
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   4. To show appreciation of; as, to recognize services by a
      testimonial.
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   5. To review; to reexamine. [Obs.] --South.
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   6. To reconnoiter. [Obs.] --R. Monro.
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   Syn: To acknowledge; avow; confess; own; allow; concede. See
        Acknowledge.
        [1913 Webster]

WordNet (r) 3.0 (2006):

recognise
    v 1: show approval or appreciation of; "My work is not
         recognized by anybody!"; "The best student was recognized
         by the Dean" [syn: recognize, recognise]
    2: grant credentials to; "The Regents officially recognized the
       new educational institution"; "recognize an academic degree"
       [syn: accredit, recognize, recognise]
    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: express greetings upon meeting someone [syn: greet,
       recognize, recognise]
    5: express obligation, thanks, or gratitude for; "We must
       acknowledge the kindness she showed towards us" [syn:
       acknowledge, recognize, recognise]
    6: be fully aware or cognizant of [syn: recognize,
       recognise, realize, realise, agnize, agnise]
    7: perceive to be the same [syn: recognize, recognise]
    8: 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]