See also: Appendix:Variations of "i"
- In second person verb conjugation, from Proto-Indo-European *h₁ésti (from *h₁es-).
- In making adjectives out of nouns, from Proto-Iranian, ultimately from Proto-Indo-European *-ikos; cognates include Sanskrit -कस (-kasa), Proto-Slavic *-ъkъ, Latin -icus, Old English -iġ, English -y.
- As an agent marker, from Proto-Iranian, cognates include Old Persian -ahya, Avestan hōi (hōi), Middle Persian -ē.
- added to adjectives to make nouns having that adjective's quality:
- added to nouns to make descriptive adjectives:
- added to place nouns to make a gendered noun of origin or nationality:
- makes names of languages from names of peoples:
- his or her:
- (Sorani) marks a third person singular agent:
- Ew be kurrekanî wit: He said to the boys
- kurrî: his son
- Pirsyarêkî lê kirdîn: He asked a question of us
- used for conjugation of the second person singular (tu):
- (oral), (nonstandard) used for present tense conjugation of the third person singular:
- ew dibêjî: he speaks
- A suffix forming infinitives of many verbs.
- Most verbs with infinitives in -î are marked by the once-inchoative infix -ăsc- in many parts of their conjugation, as well as in various derived words; two such verbs are a urî (“to hate”) and a hotărî (“to decide”).
- A sizable group of verbs have infinitives in -î but do not use the infix -ăsc-, and are otherwise fairly regular; these include, among others, the common verb a coborî (“to descend”).
- There is a variant form, -i, derived from the same Latin source.