multiplicity

mul·ti·plic·i·ty

noun \ˌməl-tə-ˈplis-ət-ē\

plural mul·ti·plic·i·ties

Definition of MULTIPLICITY

1

: the quality or state of being multiple or various

2

: the ratio of the number of infectious particles (as of a bacteriophage) to the number of cells at risk <monolayer cultures…were infected at an effective multiplicity of approximately 100—J. J. Holland>