rhizobium

noun

rhi·​zo·​bi·​um rī-ˈzō-bē-əm 

plural rhizobia rī-ˈzō-bē-ə 

: any of a genus (Rhizobium) of small heterotrophic soil bacteria capable of forming symbiotic nodules on the roots of leguminous plants and of there becoming bacteroids that fix atmospheric nitrogen

rhizobial

rī-ˈzō-bē-əl 

adjective

Word History

Etymology

New Latin, from rhiz- + Greek bios life — more at quick entry 1

First Known Use

1890, in the meaning defined above

Medical Definition

rhizobium

noun

rhi·​zo·​bi·​um rī-ˈzō-bē-əm 

1

capitalized : a genus (family Rhizobiaceae) of small heterotrophic soil bacteria capable of forming symbiotic nodules on the roots of leguminous plants where they fix atmospheric nitrogen

2

plural rhizobia -bē-ə  : any bacterium of the genus Rhizobium