n. & v.
n. 1 the testing of a metal or ore to determine its ingredients and quality. 2 Chem. etc. the determination of the content or strength of a substance.
v. 1 tr. make an assay of (a metal or ore). 2 tr. Chem. etc. perform a concentration on (a substance). 3 tr. show (content) on being assayed. 4 intr. make an assay. 5 tr. archaic attempt. Assay Office an establishment which awards hallmarks. assayer n.
[ ME f. OF assaier, assai, var. of essayer, essai: see ESSAY ]