ENGLISH
REFERENCE

assay

n. countable
C2 Proficiency US //ˈæsi// UK //ɐsˈeɪ// as·say Archaic

n. a test that checks how pure or strong a substance is, like gold or a drug. It is a formal way to describe a scientific analysis.

n. a qualitative or quantitative analysis of a substance to determine its components or purity. Frequently used in metallurgical, pharmacological, and biochemical contexts to verify the concentration of a specific ingredient.


SIMPLE

The lab performed an assay to check the purity of the gold.

CONTEXTUAL

Before the new medication could be approved, the researchers had to complete a precise assay of its active ingredients.

COMPLEX

The mining company awaited the results of the chemical assay, which would determine whether the ore vein was rich enough to justify the cost of a full-scale extraction operation.

Synonyms
Origin

From Middle English assay (noun) and assayen (verb), from Anglo-Norman assai (noun) and Anglo-Norman assaier (verb), from Old French essai. Doublet of essay.

Usage

Often paired with 'of' to specify the substance being tested.

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