Hungarian Historical Phonology ló
ló 'horse'
First attestation/Old Hungarian data
[coming]
Important dialectal forms
[coming]
Uralic/Ugric/Pre-Hungarian reconstruction
(Disputed:)
UEW: PUg *luwɜ (luγǝ) 'horse; Pferd'
Status of the Ugric etymology
Improbable (phonologically irregular)
Loan etymology
PUg ← East Iranian *loγǝ < *vlaγǝ < PIr *bāraka- (~ Middle Persian bārag 'horse') (Harmatta 1997: 72)
Possible substrate loans
Cognates suggested in earlier research
Khanty: East (V) loγ, South (DN) taw, North (O) law
Mansi: South (TJ) low, East (KU) lo, West (P) luw, North (So) luw
Commentary
No PUg form can be reconstructed; even POUg reconstruction is impossible due to irregular vocalism. As hinted already by Hajdú (1962), the Ugric words are probably loans from somewhere.
The Iranian etymology of Harmatta (1997) is based on ad hoc East Iranian reconstruction.
Conclusion
The Iranian loan etymology is unconvincing; the Ugric etymology is irregular. Possible substrate loans.
References
EWUng
Hajdú 1962
Harmatta 1997
UEW: Proto-Ugric Uralonet