In a fervid manner; with intense passion, enthusiasm, or deep feeling expressed emphatically.
From the adjective 'fervid' (Latin 'fervidus') plus the adverbial suffix '-ly', which converts adjectives into adverbs describing how an action is performed.
When someone speaks fervidly about something they believe in, you can hear the intensity in their voice—it's not just enthusiastically, it's with this consuming, almost burning quality to their words.
Complete word intelligence in one call. Free tier — 50 lookups/day.