Quirk or Quirkiness

[belly_ttt]

What is the difference between "quirk" and "quirkiness"?

[Hi_there_Carl]

A quirk is a peculiar trait.
Quirky, is a way to describe a persons behavior when their behavior is peculiar and quirkiness is a state of being quirky.

The forms of quirk are:

quirk·i·ly adverb quirk·i·ness noun
quirk·ish adjective
quirky adjective

The suffix -ness, which goes back to Old English, continues to have a productive life. It commonly attaches to adjectives in order to form abstract nouns, such as artfulness and destructiveness. The suffix -ness also forms nouns from adjectives made of participles, such as contentedness and willingness. It can also form nouns from compound adjectives, such as kindheartedness and straightforwardness. The suffix -ness can even be used with phrases: matter-of-factness.

Quirkiness is a noun formed from the adjective "quirky"