assay vs succeed

assay is a noun but succeed is not a noun.

Word	Noun	Adjective	Verb	Adverb
assay	Yes	No	Yes	No
succeed	No	No	Yes	No

assay (noun)	succeed (noun)
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.
an appraisal of the state of affairs
a written report of the results of an analysis of the composition of some substance
a substance that is undergoing an analysis of its components

assay (verb)	succeed (verb)
analyze (chemical substances)	attain success or reach a desired goal
make an effort or attempt	be the successor (of)