Merriam-Webster Collegiate Dictionary - dissuade

 transitive verb  (~d; dissuading)  Etymology: Middle French or Latin; Middle French ~r, from Latin dissuadere, from dis- + suadere to urge — more at sweet  Date: 15th century  1.  a. to advise (a person) against something  b. archaic to advise against (an action)  2. to turn from something by persuasion unable to ~ him from going  • ~r noun