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Webster 1913 Edition

Noun.

Quality or state of being nice.

Noun.

Delicacy of perception; the quality of perceiving small differences; as niceness of taste.

Extreme delicacy; excess of scrupulousness or exactness.

Unlike the niceness of our modern dames.

Accuracy; minute exactness; as niceness of work; niceness of texture or proportion.

Wheres now the labored niceness in thy dress?

niceness ‎(countable and uncountable, plural nicenesses)

(obsolete) Silliness; folly. [16th c.]
Effeminacy; indulgence in soft living or luxuriousness. [from 16th c.]
- 1603, John Florio, translating Michel de Montaigne, Essayes, London: Edward Blount, OCLC 946730821, II.10:
  He was a good Citizen, of an honest-gentle nature, as are commonly fat and burly men; for so was he: But to speake truely of him, full of ambitious vanitie and remisse nicenesse [transl. mollesse].
(obsolete) Shyness; reserve. [16th-19th c.]
Fastidiousness; fine sensitivity. [from 17th c.]
Pleasantness, especially of behaviour or personality; agreeableness. [from 19th c.]
(computing, Unix) A value determining how much processor time to concede to a running process. (See also nice ‎(verb), renice.)