Dissuade, Deter, Discourage, Divert mean to turn one aside from a purpose, a project, or a plan.
Dissuade carries the strongest implication of advice, argument, or exhortation; like the affirmative form persuade, it usually suggests gentle or effective methods and carries no suggestion of bullying or browbeating, though it equally carries little or no suggestion of coaxing or wheedling.
While deter often implies the operation of fear as the cause of turning aside from the fulfillment of a project, it may suggest no more than a changing of purpose for cause rather than from mere caprice.
In deterrent the implication that it is fear which is the cause of holding back is stronger than in the verb.
Discourage (see also DISCOURAGE) implies a deterring by undermining spirit or enthusiasm or by weakening intent or sense of purpose.
Divert (see also TURN and AMUSE) implies a turning aside, but here the mind or some of its functions is usually the thing diverted or turned aside, and another object of interest or attention is generally expressed or understood as the alternative; in this sense divert is often used of the very young, or of the preoccupied or the worried.