Definition of opines:
(v) :
(intransitive, transitive) To express an opinion; to state as an opinion; to suppose, consider (that).
(v) :
(intransitive) To give one's formal opinion (on or upon something).
(v) :
(intransitive, transitive) to suppose, consider as correct, or entertain, an opinion.
(n) :
(biochemistry) Any of a class of organic compounds, derived from amino acids, found in some plant galls.