ŏpīnātĭo (noun F) : id.
* A supposing, opining; a supposition, conjecture, imagination, fancy, opinion, belief (class.): opinationem volunt esse imbecillam assensionem,Cic. Tusc. 4, 7, 15; id. Ac. 2, 25, 78: haec autem opinatio est judicatio se scire, quod nesciat,id. Tusc. 4, 11, 26; cf. the context: mordax et inepta,Val. Max. 1, 8, 8: (Tullius) quid super tali opinatione sentiret,Arn. 3, 6.

s. TLL