Hungarian Historical Phonology jó
jó: java- 'good'
First attestation/Old Hungarian data
[coming]
Important dialectal forms
[coming]
Uralic/Ugric/Pre-Hungarian reconstruction
(Obsolete:)
UEW: PUg *jomɜ- (jamɜ-) 'good; gut'
Status of the Ugric etymology
[coming]
Loan etymology
None suggested
Cognates suggested in earlier research
Khanty: East (V) jĕm, South (DN) jĕm, North (O) jim 'good' < Proto-Khanty ?
Mansi: South (TJ) jomā·s, East (KU) joməs, West P joms 'good', North (So) jomas 'good' < ? Proto-Mansi *jɔmas
Commentary
The vowel-correspondences are irregular: even the correspondences within Khanty dialects are irregular (according to UEW the Proto-Khanty front vowel is caused by *j-, but this does not explain the aberrant correspondences in different dialects). The Ob-Ugric comparanda is listed by Honti (1982) among the words that cannot be reconstructed to Proto-Ob-Ugric (no 738.)
Conclusion
A Proto-Ugric reconstruction is impossible; the words can be parallel substrate loans.
References
EWUng
Honti 1982
UEW: Proto-Ugric Uralonet