In Latin nouns with suffix -o:r (e.g. ardor, honor/hono:s, rubor) are usually linked to verbs, rubere, ardere, etc. How many examples are known similar to *h2euso:s "dawn" and *bhleh2o:s "flower". As goddesses, these names are Aurora and Flora, and Greek and Sanskrit cognates confirm H2euso:s as a PIE theonym. What's the relation between masculine/feminine -o:s- and neuter -os-? Should we assume PIE *h2eus-o:s < older *h2ewso- < *h2ewos- ?
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