n, pl  -ties  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 of approximately 100 -J. J. Holland>  .
 
 
 
Published under license with Merriam-Webster, Incorporated.  © 1997-2024.