perfervid\per-FER-vid\
adjective
:marked by overwrought or exaggerated emotion
:excessively fervent

The group’s leaders have done little to distance themselves from the actions of their angrier and more perfervid followers.

“Biron has struggled to make the Dostoevsky apartment a center for the perpetual and perfervid enthusiasm for the author that animates Russians.” — From an article by Philip Kennicott inThe Washington Post, October 21, 2012

The adjectives “fervent,” “fervid,” and “perfervid” all derive from the Latin verb “fervēre,” meaning “to boil,” and suggest a bubbling up of intense feeling. “Fervent” was the first to enter the English language in the 14th century. It stresses sincerity and steadiness of emotional warmth and zeal, as in “Her colleagues expressed fervent good wishes.” The next to emerge was “fervid” in the late 16th century. It too suggests warmth but adds an element of spontaneity and feverishness. A lover might write a fervid billet-doux to his beloved, for example. With its first known appearance in print dating back only to 1833, “perfervid” is a relative newcomer to English, but it implies the most extreme or exaggerated expression of emotion. Its intensity comes from “per-,” a prefix meaning “thoroughly.”

Words provided by Merriam-Webster.com