käyttöösi

käyttöösi is a Finnish phrase that literally translates to “for your use” or “to be used by you.” It is formed from the verb “käyttää” (to use) with the suffix “‑ön” (in‑use) and the second‑person pronoun “sinun” turned possessive, which in the genitive form is “si‑” and linked as a part of the word. The genitive marker “-si” indicates possession, so together the phrase conveys that the object or service is intended for the listener’s utilization.

The phrase is typically used in contexts where a product, service, or resource is being handed over, installed, or prepared for someone’s personal use. For example, a technician might say “Kun asennus on valmis, laitteen käyttöösi on varsinainen käyttökuitta” meaning “Once the installation is complete, the device is ready for your use, with an official usage certificate.” It can also be employed in more abstract contexts, such as “Tarjoamme sinulle täyden tukipalvelun käyttöösi” (We offer you full support service for your use).

While similar phrases exist in other Uralic languages (for instance, Estonian "kasutamiseks" or Hungarian "használatodra"), the construction with the possessive suffix is particularly characteristic of Finnish. The expression exemplifies how Finnish combines verb stems, case endings, and possessives to create precise, context‑aware meanings.