FERVIDLY
fierily, fervently, fervidly
(adverb) with passionate fervor; āboth those for and against are fervently convinced they speak for the great majority of the peopleā; āa fierily opinionated bookā
Source: WordNet® 3.1
Etymology
Adverb
fervidly (comparative more fervidly, superlative most fervidly)
In a fervid manner.
Source: Wiktionary
FERVID
Fer"vid, a. Etym: [L. fervidus, fr. fervere. See Fervent.]
1. Very hot; burning; boiling.
The mounted sun Shot down direct his fervid rays. Milton.
2. Ardent; vehement; zealous.
The fervid wishes, holy fires. Parnell.
– Fer"vid*ly, adv.
– Fer"vid*ness, n.
Source: Webster’s Unabridged Dictionary 1913 Edition