to change repeatedly one's attitude or opinions with respect to a cause, subject, etc.; equivocate.
2.
to turn renegade.
Origin: 1645–55; < Latin tergiversātus (past participle of tergiversārī to turn one's back), equivalent to tergi- (combining form of tergum back) + versātus, past participle of versāre, frequentative of vertere to turn; see -ate1