Nouns

(n)ardor, ardour, elan, zeala feeling of strong eagerness (usually in favor of a person or cause)“they were imbued with a revolutionary ardor”, “he felt a kind of religious zeal”
(n)ardor, ardourintense feeling of love
(n)ardor, ardour, fervor, fervour, fervency, fire, fervidnessfeelings of great warmth and intensity“he spoke with great ardor”