Micturate

micturate \ˈmik-chə-ˌrāt, ˈmik-tə-\ intransitive verb: urinate

Etymology: Latin micturire to desire to urinate, from meiere to urinate

According to Merriam-Webster there’s not a shade of difference in meaning between micturate and urinate, but I wonder if there might be in the real world. Wikipedia’s entry on urination uses the term micturation whenever it describes the physiology of voiding oneself, so perhaps micturate is more a scientific term and urinate an everyday word.