plural noun
Rhi·​zo·​bi·​a·​ce·​ae | \ (ˌ)rīˌzōbēˈāsēˌē \

Definition of Rhizobiaceae

: a small family of rod-shaped or irregular usually flagellated and gram-negative aerobic bacteria (order Rhizobiales) that includes saprophytes, important nitrogen-fixing symbionts of plants, and some plant pathogens — see agrobacterium , rhizobium

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History and Etymology for Rhizobiaceae

New Latin, from Rhizobium, type genus + -aceae

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Cite this Entry

“Rhizobiaceae.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/Rhizobiaceae. Accessed 15 December 2019.

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