Etymology Borrowed from Middle French opiner, from Latin opīnor (“to hold as an opinion”), from *opīnus (“thinking, expecting”), only in negative nec-opīnus (“not expecting”) and in-opīnus (“not expected”); akin to optō (“to choose, desire”), and to apīscor (“to obtain”); see optate and opt.
1
To express an opinion; to state as an opinion; to suppose, consider (that).
I opined that matters would soon become considerably worse.
"Your decisions," she opined, "have been unfailingly disastrous for this company."
1 more example
Requested “Bonsoir, Paris!” and he performed with such élan I pressed a crisp five-franc note into his hand. He removed his dark glasses, checked the watermark, invoked his pet saint’s name, gathered his coppers, and scarpered through the flower beds, laughing like a madcap. Whoever opined “Money can’t buy you happiness” obviously had far too much of the stuff.2004, David Mitchell, “Letters From Zedelghem”, in Cloud Atlas, →ISBN, page 75:
2
To give one's formal opinion (on or upon something).
I had to opine on the situation because I thought a different perspective was in order.
3
To suppose, consider as correct, or entertain, an opinion.
Do you, Maister Francis, opine that ye will re-establish your father's credit by cutting your kinsman's thrapple, or getting your ain sneckit instead thereof in the College-yards of Glasgow?1817 December 31 (indicated as 1818), [Walter Scott], Rob Roy. […], volume (please specify |volume=I to III), Edinburgh: […] James Ballantyne and Co. for Archibald Constable and Co. […]; London: Longman, Hurst, Rees, Orme, and Brown, →OCLC:
This, I opine, is a correct and fair statement of the case.1870, Pennsylvanian College of Dental Surgery, The Dental Times, Vol VII p 130:
Etymology Derived from Ancient Greek ὀπός (opós, “juice of a plant”) + -ine.
1
Biochemistry, Biology, Chemistry, Microbiology, Natural sciences, Physical sciences Any of a class of organic compounds, derived from amino acids, found in some plant galls.