Definition of Assay

Noun: assay 'a,sey

An appraisal of the state of affairs
"they made an assay of the contents";
- check
A substance that is undergoing an analysis of its components
A written report of the results of an analysis of the composition of some substance
A quantitative or qualitative test of a substance (especially an ore or a drug) to determine its components; frequently used to test for the presence or concentration of infectious agents or antibodies etc.

Verb: assay 'a,sey

Analyse (chemical substances)
Make an effort to accomplish something
"He assayed to shake off his fears";
- try, seek, attempt, essay