different between stoutness vs validity

English

From stout +? -ness

stoutness (countable and uncountable, plural stoutnesses)

(usually uncountable) The state or quality of being stout.
(countable, rare) The result or product of being stout. (Can we add an example for this sense?)

valid +? -ity, borrowed from Middle French validité, from Late Latin validitas.

validity (countable and uncountable, plural validities)

The state of being valid, authentic or genuine.
State of having legal force.
A quality of a measurement indicating the degree to which the measure reflects the underlying construct, that is, whether it measures what it purports to measure (see reliability).

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