teoriyi
Teoriyi is the definite accusative form of the Turkish noun teori, meaning theory. In Turkish, theories and other abstract concepts are treated as countable nouns that can take the accusative case when they function as direct objects. The suffix -yi (with vowel harmonious variants -yi, -yı, -yu, -yü) marks definiteness and the direct object. In practice, teoriyi appears in sentences such as Bu teoriyi okudum (I read this theory) or Teoriyi savundular (They defended the theory).
Etymology and usage. The Turkish word teori is a loanword derived from Western languages, most likely French
Related forms. The plural of teori is teoriler, and its definite direct object plural form is teorileri.
See also. Theory in other languages; theoretical and theoretical frameworks; hypotheses; epistemology.
Notes. Turkish nouns do not require articles; definiteness is shown through suffixes like -yi for the accusative