The Collaborative International Dictionary of English v.0.48:

Agnize \Ag*nize"\ ([a^]g*n[imac]z"), v. t. [Formed like
   recognize, fr. L. agnoscere.]
   To recognize; to acknowledge. [Archaic]
   [1913 Webster]

         I do agnize a natural and prompt alacrity. --Shak.
   [1913 Webster]

WordNet (r) 3.0 (2006):

agnize
    v 1: be fully aware or cognizant of [syn: recognize,
         recognise, realize, realise, agnize, agnise]