noun

1. an examination or testing
2. the analysis of an ore, alloy, drug, etc. to determine the nature, proportion, or purity of the ingredients
3. a substance to be thus tested or analyzed
4. the result or report of such an analysis
5. Now Rare an attempt

Etymology: ME & Anglo-Fr assai < OFr essai, trial: see essay, n.

transitive verb

1. to make an assay of; test; analyze
2. to attempt

intransitive verb