原始印度-伊朗語
后續語音改變

從原始印度-伊朗語分離出印度-雅利安語的語音變更是濁咝擦音 *z 的消失。印度-雅利安語中清送氣音 ph, th, kh 起源的最普遍接受的說法是它們來自清塞音加上喉音，這是索緒爾在1891年最初提出來的。例如梵語的  來自原始印歐語的 steh₂-。同源於拉丁語的 , 古希臘語的 ἵστημι()。
分離出伊朗語的是 PIE 的濁送氣音的不送氣化。伊朗語的創新是產生了一個擦音系列 f, θ, x，在多數情況下它們演變自在輔音之前位置上的清塞音 p, t, k，但它們還所有位置上對應於印度-雅利安語的清送氣塞音 ph, th, kh。在新阿維斯陀語中，濁塞音在詞中位置上除了在鼻音和噝擦音之後以外大量擦音化為 β, δ, γ。
| PIE | PIE | OInd/VS | Av | PIE | OInd/VS | Av   |
| --- | --- | --- | --- | --- | --- | --- |
| *p | > | p | p | *ph̥atēr "father" | pitā́ "father" | pitar- "father"   |
| *b | > | b | b | *bel- "strong" | bálam "strength" | -   |
| *bh | > | bh | b | *bhréhatēr "brother" | bhrā́tār- "brother" | brātar- "brother   |
| *t | > | t | t | *tuhxóm "thou" | tuvám "thou" | tvəm "thou"   |
| *d | > | d | d | *doru "wood" | dā́ru "wood" | dāru- "wood"   |
| *dh | > | dh | d | *dhohxneha- "grain" | dhānā́- "grain" | dāna- "grain"   |
| *k̂ | > | ś | s | *dék̂m̥ "ten" | dáśa "ten" | dasa "ten"   |
| *ĝ | > | j | z | *ĝónu "knee" | jā́nu "knee" | zānu- "knee"   |
| *ĝh | > | h | z | *ĝhimós "cold" | himá- "cold, frost" | zəmaka- "winterstorm"   |
| *k | > | k ~ c | x ~ č | *kruharós "bloody" | krūrá- "bloody" | xrūra- "bloody"   |
|  |  |  |  | *téket "may he run" | - | tačat̰ "may he run"   |
| *g | > | g ~ j | g ~ ǰ | *haéuges- "strength" | ójas- "strength" | aoǰah "strength"   |
|  |  |  |  | *haugrós "strong" | ugrá- "strong" | ugra- "strong"   |
| *gh | > | gh ~ h | g ~ ǰ | *dl̥hxghós "long" | dīrghá- "long" | darəga- "long"   |
|  |  |  |  | *dlehxghistos "longest" | - | draǰišta- "longest"   |
| *kw | > | k ~ c | k ~ č | *kwós "who" | káḥ "who" | kō "who"   |
|  |  |  |  | *kwe "and" | ca "and" | ́ča "and"    |
| *gw | > | g ~ j | g ~ ǰ | *gwou- "cow" | gav- "cow" | gau- "cow"   |
|  |  |  |  | *gwih3uós "alive" | jīvá- "alive" | OPer: ǰīva- "living"   |
| *gwh | > | gh ~ h | g ~ ǰ | *gwhnénti "strike" (pl.) | ghnánti "strike" (pl.) | -   |
|  |  |  |  | *gwhénti "strikes" | hánti "strikes" | ǰainti "strikes"   |
| *s | > | s | s ~ h | *septm̥ "seven" | saptá "seven" | hapta "seven"   |
|  |  |  |  | *asti "is" | asti "is" | asti "is"   |
| *i̥ | > | y | y | *i̥ugóm "yoke" | yugam "yoke" | yuga- "yoke"   |
| *u̥ | > | v | v | *u̥éĝheti "drives, rides" | váhati "drives" | vazaiti "travels"   |
| *m | > | m | m | *méhatēr "mother" | mātár- "mother" | mātar- "mother"   |
| *n | > | n | n | *nos "us" | nas "us" | nō "us"   |
| *n̥ | > | a | a | *n̥- "un-" | a- "un-" | a- "un-"   |
| *m̥ | > | a | a | *k̂m̥tóm "hundred" | satám "hundred" | satəm "hundred"   |
| *l̥ | > | r̥ | əhr | *u̥l̥kwos "wolf" | vĺ̥ka- "wolf" | vəhrka- "wolf"   |
| *r̥ | > | r̥ | ərə | *k̂r̥d- "heart" | hŕ̥d- "heart" | zərəd- "heart"   |
| *i | > | i | i | *linékwti "leaves" | riṇákti "leaves" | irinaxti "releases"   |
| *e | > | a | a | *dék̂m̥ "ten" | dáśa "ten" | dasa "ten"   |
| *ē | > | ā | ā | *hanḗr "man" | nā "man" | nā "man"   |
| *a | > | a | a | *haéĝeti "drives" | ájati "drives" | azaiti "drives"   |
| *ā | > | ā | ā | *méhatēr "mother" | mātā́ "mother" | mātar- "mother"   |
| *o | > | a ~ ā | a ~ ā | *ĝómbhos "tooth, peg" | jā́mbha- "tooth, tusk" | -   |
|  |  |  |  | *ĝónu "knee" | jānu "knee" | zānu- "knee"   |
| *ō | > | ā | ā | *dhohxneha- "grain" | dhānā́- "grain" | dāna- "grain"   |
| *u | > | u | u | *iugóm "yoke" | yugám "yoke" | yuga- "yoke"   |
| *ū | > | ū | ū | *mū́s "mouse" | mū́ṣ- "mouse" | NPer mūs "mouse"   |
| *h1 | > | ⊘ | ⊘ | *h1ésti "is" | ásti "is" | asti "is"   |
| *h2 | > | ⊘ | ⊘ | *h2r̥tk̂os "bear" | r̥kṣa- "bear" | arəša- "bear"   |
| *h3 | > | ⊘ | ⊘ | *h3ókws(i) "eye" | ákṣi "eye" | aši "eye"   |
| *h4 | > | ⊘ | ⊘ | *h4órĝhis "testicle" | - | ərəzi- "testicle"   |
| 原始印度-伊朗語 | OP, Av | OInd/VS |
| --- | --- | --- |
| *açva ("horse") | Av, OP aspa | aśva |
| *bhag- | OP baj- (bāji; "tribute") | bhag- (bhaga) |
| *bhrātr- ("brother") | OP brātar | bhrātṛ |
| *bhūmī ("earth", "land") | OP būmi | bhūmī |
| *martja ("mortal, "man") | OP martya | martya |
| *māsa ("moon") | OP māha | māsa |
| *vāsara ("early") | OP vāhara ("spring") | vāsara ("morning") |
| *arta ("truth") | Av aša, OP arta | ṛta |
| *draugh- ("falsehood") | Av druj, OP draug- | druh- |
| *sauma "pressed (juice)" | Av haoma | soma |