bi·o·as·say 
(bī′ō-ăsā′, -ă-sā)
(bī′ō-ăsā′, -ă-sā)n.
1. Determination of the strength or biological activity of a substance, such as a drug, by comparing its effects with those of a standard preparation on a test organism.
2. A test used to determine such strength or activity.
tr.v. bi·o·as·sayed, bi·o·as·say·ing, bi·o·as·says
To cause to undergo a bioassay.