Countable Nouns That Start with R and End with IUM

Explore 11 verified English countable nouns starting with R and ending with IUM, including Rhizobium, Refugium, Radiostrontium, Rosarium, Reptilium, Resilium and Rhynchosporium. 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 RA
2 words
radiostrontium
ranarium
Starts with RE5 words
refugium
reptilium
resilium
respiratorium
restibrachium
Starts with RH3 words
rhizobium
rhynchosporium
rhipidium
Starts with RO
1 words
rosarium

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