Comments: PN *=ōʁ- is the terminative stem; durative (with infix and Ablaut) *=ē-b-ʁ- is reflected in Chech. =īʁ- (with the same meaning).
The intransitive Ablaut correlate with *-ā- is PN *=āʁ- 'to sit'. Vowel length here can be established by the Ing. pret. =äʁaw. In Bacb. the root is preserved in the compound ʕe=aʁ- "to sit". This is one of the relatively rare cases of the *a/*o "intransitive/ transitive" Ablaut in PN.