töösi

Tõsi is an Estonian noun meaning truth, truthfulness, or the correctness of a statement. It is used to indicate that something corresponds to reality or is factually accurate. In everyday language it appears in sentences such as "See on tõsi" (That is true) and in technical contexts as "tõeväärtus" (truth value), a term used in logic and philosophy to denote whether a statement is true or false.

Tõsi is often contrasted with the related noun tõde, which also translates as truth but is more commonly used to refer to truth as a general concept or principle. In ordinary speech the two terms can overlap, but tõde tends to denote truth as an idea, while tõsi focuses on the factual correctness of a specific claim within a given context.

The word is a basic part of Estonian vocabulary and appears across everyday speech, journalism, literature, and education. It participates in a range of expressions and is complemented by other related forms and compounds used to discuss accuracy, evidence, and belief.

See also: tõde, tõeväärtus.