Ardor

Ar·dor

Ardor

n.
  1. Heat, in a literal sense; as, the ardor of the sun's rays.
  2. Warmth or heat of passion or affection; eagerness; zeal; as, he pursues study with ardor; the fought with ardor; martial ardor.
  3. Bright and effulgent spirits; seraphim. [Thus used by Milton.]