The Collaborative International Dictionary of English v.0.48:

Urgent \Ur"gent\, a. [L. urgens, p. pr. of urgere: cf. F.
   urgent. See Urge.]
   Urging; pressing; besetting; plying, with importunity;
   calling for immediate attention; instantly important. "The
   urgent hour." --Shak.
   [1913 Webster]

         Some urgent cause to ordain the contrary. --Hooker.
   [1913 Webster]

         The Egyptians were urgent upon the people that they
         might send them out of the land in haste. --Ex. xii.
                                                  33.
   [1913 Webster]

WordNet (r) 3.0 (2006):

urgent
    adj 1: compelling immediate action; "too pressing to permit of
           longer delay"; "the urgent words `Hurry! Hurry!'";
           "bridges in urgent need of repair" [syn: pressing,
           urgent]