The quality of being crisp; the state of being firm, brittle, fresh, or clearly defined.
From 'crisp' plus the noun-forming suffix '-ness,' dating to Old English. This suffix creates abstract nouns describing the essential quality of adjectives.
Interestingly, 'crispness' can describe both physical qualities (the crispness of fried chicken) and abstract ones (the crispness of his response), showing how English lets one word express completely different senses.
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