/
əˈseɪ, 
ˈaseɪ/
n.
  - the testing of a metal or ore to determine its ingredients and quality.
 - a procedure for measuring the biochemical or immunological activity of a sample.
 
v.
  - carry out an assay on.
 - archaic attempt.
 
Derivative
Etymology
ME: from OFr. assai (n.), assaier (v.), var. of essai ‘trial’, essayer (see essay).