Countable Nouns That Start with O and End with RUS

Explore 4 verified English countable nouns starting with O and ending with RUS, including Organophosphorus, Oncovirus, Orthomyxovirus and Oncornavirus. Sort these count nouns with singular and plural forms by word length for ESL grammar practice, determiner usage, and plural spelling below, or review singular and plural count rules in our noun grammar guide.

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Starts with ON
2 words
oncovirus
oncornavirus
Starts with OR
2 words
organophosphorus
orthomyxovirus

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