Bioassay

US: (n. bī′ō ə sā′, -as′ā; v. bī′ō ə sā′)

Inflections of 'bioassay' (v): (⇒ conjugate)

bioassays

v 3rd person singular

bioassaying

v pres p

bioassayed

v past

bioassayed

v past p

WordReference Random House Unabridged Dictionary of American English © 2026

bi•o•as•say  (n. bī′ō ə sā′, -as′ā;v. bī′ō ə sā′), n., v., -sayed, -say•ing. 
n. 

1. Laboratory determination of the biological activity or potency of a substance, as a vitamin or hormone, by testing its effect on the growth of an organism.

v.t. 

2. Laboratory to subject to a bioassay.

• bio(logical) + assay 1910–15

Collins Concise English Dictionary © HarperCollins Publishers::

bioassay noun / ˌbaɪəʊəˈseɪ -ˈæseɪ/

1. a method of determining the concentration, activity, or effect of a change to substance by testing its effect on a living organism and comparing this with the activity of an agreed standard

verb / ˌbaɪəʊəˈseɪ/

1. (transitive) to subject to a bioassay