I. |bī(ˌ)ō+ noun
Etymology: bio logical assay
: determination of the relative effective strength of a substance (as a vitamin, hormone, or drug) by comparing its effect on a test organism with that of a standard preparation ; also : a particular test of this kind
do a bioassay on the sample
II. |bī(ˌ)ō+ transitive verb
: to perform a bioassay on