1. feelings of great warmth and intensity

    e.g. he spoke with great ardor

    Synonym: ardorfervorfervourfervencyfirefervidness

2. intense feeling of love

    Synonym: ardor

3. a feeling of strong eagerness (usually in favor of a person or cause)

    e.g. they were imbued with a revolutionary ardor
           he felt a kind of religious zeal

    Synonym: ardorelanzeal