Source : Webster's Revised Unabridged Dictionary (1913)

Micturition \Mic`tu*ri"tion\, n. [L. micturire to desire to make
   water, v. desid. fr. mingere, mictum, to make water.]
   The act of voiding urine; also, a morbidly frequent passing
   of the urine, in consequence of disease.

Source : WordNet®

micturition
     n : the discharge of urine [syn: {urination}]