Synonyms: cynical, misanthropic, misanthropical
Definition: believing the worst of human nature and motives; having a sneering disbelief in e.g. selflessness of others
Similar words: distrustful
Definition: having or showing distrust
Usage: a man of distrustful nature; my experience...in other fields of law has made me distrustful of rules of thumb generally- B.N.Cardozo; vigilant and distrustful superintendence- Thomas Jefferson