This paper aims at comparing Hapax Legomenons encountered in Gerard Clauson’s Etymological Dictionary (ED) with Yakut language. This comparision is restricted to Hapax Legomenons starting with vowels. The results of this study show that the Qarakhanid Hap. leg.’s açlın- “to open”, emigle- “to hit on the breast” and etle- “to fatten”, etlet- “to order to be fatten”, ısrım “(for man) wrinkled and frowning”, ıtla- “to reckon someone to belong to the dog family”, *imlen“to be beckoned”, imlet- “to order to be beckoned”, isigle- “to walk in the summer heat”, itlin- “to be pushed”, oçaklan- “to have a fireplace”, oluk II “(a horses) withers”, ordulan- “to choose a place for himself as his capital”, öküzlen- “to own a bull”, üçlen- “to become three”, and maybe the Old Uigur Hap. leg. emsi- “(for mouth) to water” indeed survive in the vocabulary of Yakut although Clauson (1972) qualified them as Hap. leg.’s in his Etymological Dictionary. Afterwards, the Hap. leg.’s emigle-, etle-, etlet-, and isigle- were attested in another languages, either. The other Hap. leg.’s imlet- “to order to be beckoned” and irtet- “to have something search for” were attested by Sleptsov (1972) which was impossible for Clauson to refer, and the words lost the characteristic of being Hap. leg.’s.