Coolness

1. The state of being cool; a moderate degree of cold; a moderate degree, or a want, of passion; want of ardor, zeal, or affection; calmness.

2. Calm impudence; self-possession. [Colloq.]

noun

1. Relative lack of physical warmth: chill, chilliness, cold, coldness. See hot/cold/lukewarm.
2. A stable, calm state of the emotions: aplomb, balance, collectedness, composure, equanimity, imperturbability, imperturbableness, nonchalance, poise, sang-froid, self-possession, unflappability. Slang cool. See calm/agitation, feelings.

The noun has 4 meanings:

Meaning #1: the property of being moderately cold
  Synonym: chilliness

Meaning #2: calm and unruffled self-assurance
  Synonyms: imperturbability, imperturbableness

Meaning #3: fearless self-possession in the face of danger
  Synonym: nervelessness

Meaning #4: a lack of affection or enthusiasm
  Synonyms: coldness, frigidity