Mektubun
Mektubun is a Turkish word that functions as the second-person singular possessive form of mektup, meaning "your letter." In this construction, the stem mektup combines with the possessive suffix -un, and due to Turkish consonant harmony the final p typically becomes b before the suffix, resulting in mektubun. The form is used to indicate ownership of a letter by the person being addressed.
Etymology and meaning trace the term to the word mektup, itself borrowed from Arabic maktūb meaning "written"
Usage and grammar: Mektubun is used in sentences to attribute the letter to the addressee. Examples include
See also: mektup, which refers to a general letter or epistolary communication; maktūb, the original Arabic root