Origins
The English word "opinion" traces its origins to the Latin term opīniō, which encompassed meanings such as "opinion," "conjecture," "belief," and "reputation." This Latin noun derived from the verb opīnārī, meaning "to think," "to believe," "to suppose," or "to conjecture." The verb opīnārī itself is likely connected to the Latin optāre, "to choose" or "to wish for," which points to a deeper etymological root in the Proto-Indo-European (PIE) root *op-, meaning "to choose," "to select," or "to prefer."
This PIE root *op- is significant in several related Latin words that revolve around the concept of choice or preference. For example, optio, meaning "choice" or "the right to choose," and optimus, meaning "best" or "most chosen," both derive from this root. English words such as "opt," "option," and "adopt" also share this lineage, underscoring the semantic field of selection and preference inherent in the root *op-. Thus, etymologically, an "opinion" is something chosen—a belief or view selected rather than a fact passively received.
The Latin opīniō had a broader semantic range than the modern English "opinion." It could refer not only to private belief or conjecture but also to public reputation—what others think of a person or thing. This duality is preserved in the English phrase "in my opinion," which signals that the statement is a chosen perspective rather than an established fact. The related Latin verb opīnor, meaning "I suppose," implies a provisional or tentative belief, something held pending further evidence or confirmation.
Middle English
The word entered English in the 14th century, borrowed from Old French opinion, which itself came from Latin opīniō. The Old French form retained much of the Latin meaning, encompassing notions of belief, judgment, and reputation. The adoption into English reflects the transmission of the concept of a subjective judgment or belief, distinct from objective knowledge.
the connection between opīnārī and optāre, and thus to the PIE root *op-, while widely accepted, is not absolutely certain. The semantic link between "to think" or "to suppose" and "to choose" is plausible but not definitively established by direct evidence. Nevertheless, the shared root provides a coherent explanation for the conceptual development of "opinion" as a chosen or selected belief.
"opinion" in English descends from Latin opīniō, itself from opīnārī, with probable etymological ties to the PIE root *op-, meaning "to choose." This lineage highlights the notion of opinion as a selected or chosen belief, rather than an objective fact. The Latin term's broader semantic range, including public reputation and provisional belief, informs the modern English usage, which emphasizes subjective judgment or personal view. The word's entry into English in the 14th century via Old French marks its integration into the language as a term for a considered, though not necessarily factual, judgment.