In the transition of Persian from Old to Middle Persian and finally to New Persian, there is a significant phonemic change: the reduction of vowel-consonant-vowel (VCV) sequence to either of the vowels. During this process, the consonant and the other vowel are omitted.

Avestan /
Old Persian
Middle Persian New Persian
šîyâ šâ šâ
čavant čant čand
duvar dar dar
âyaθîya šâha → šâh šâh

Dialects of New Persian

VCV phoneme reduction has occurred within New Persian as well. There are many reductions both in standard dialect and regional dialects. Interestingly, in some dialects, a different vowel has left the sequence, resulting in having, for example, both “mînam” and “monam” as the reduced forms of “mîkonam”.

Full Form Reduced Form
pîrâhan pîran
nevardebâm nardebâm
xwâhar xwâr
barâdar barâr
xodemûn xomûn

Reduction in Conjugation

VCV reduction is extensively found in the conjugation of verbs in spoken Persian:

Full Form Reduced Form
mîšavam mîšam
mîravam mîram
mîxwâham mîxwâm
mîdaham mîdam
mîtavânam mîtânam → mîtûnam
mîgûyam mîgam, mîgûm
mîyâvaram mîyâram
mîyâyam
mîgâyad
mîzâyad
mîyâm
mîgâd
mîzâd
mîgozâram mîzâram
mîkonam mînam, monam
mîbînam mînam
mîdânam mînam
rafte bûdam raftûdam