What is the meaning of T-?

tertiary form

Used together with the suffix to create feminine agent nouns.

Alternative form of et

cislocative, indicating motion towards the speaker

you (singular object pronoun)

Marks a noun as having a reflexive possessor, referring back to the same entity as another element in the clause.

Marks a postposition as having a reflexive object, referring back to the same entity as another element in the clause.

Marks a verb in a verb form that takes series II markers as having a reflexive argument, referring back to the same entity as another element in the clause.

Marks an unspecified person when obligatorily used with the adverbializers -e, -emje, and -ke, forming circumfixes t- -e, t- -emje, and t- -ke.

Marks a transitive verb as having a third-person patient/object with verb forms that take series II markers for a small group of verbs, namely those whose roots start with a consonantless open syllable ü or ö.

With following vowel lengthened if in an unreduced open syllable.

Marker of t-prothesis

Marker of lenition of s after the definite article

Alternative form of il-

Marker of t-prothesis

Marker of lenition of s after the definite article

Source: wiktionary.org