Noun
Heat, in a literal sense; as, the ardor of the sun's rays.
Warmth or heat of passion or affection; eagerness; zeal; as, he pursues study with ardor; the fought with ardor; martial ardor.
Bright and effulgent spirits; seraphim.
Source: Webster's dictionaryLearning is not attained by chance. It must be sought for with ardor and attended to with diligence. Abigail Adams
Tolerance - the function of an extinguished ardor - tolerance cannot seduce the young. Emil Cioran
It is the unknown that excites the ardor of scholars, who, in the known alone, would shrivel up with boredom. Wallace Stevens
It must be thoroughly understood that war is a necessity, and that the more readily we accept it, the less will be the ardor of our opponents, and that out of the greatest dangers communities and individuals acquire the greatest glory. Thucydides
A fire will sear and the sun burn yet more, but neither can match the ardor of a man's heart. Indonesian Proverb
The ardor of parental affection consumes the heart with its fire. American Proverb