The difference between Eager and Perfervid

When used as adjectives, eager means sharp, whereas perfervid means extremely, excessively, or feverishly passionate.

Eager is also noun with the meaning: (tidal bore).

check bellow for the other definitions of Eager and Perfervid

Eager as an adjective (obsolete):

Sharp; sour; acid.
Eager as an adjective (obsolete):

Sharp; keen; bitter; severe.
Eager as an adjective:

Desirous; keen to do or obtain something.

Examples:

"The hounds were eager in the chase."

"I was eager to show my teacher how much I'd learned over the holidays."

"You stayed up all night to get to the front of the queue. You must be very eager to get tickets."
Eager as an adjective:

Brittle; inflexible; not ductile.
Eager as an adjective (comptheory):

Not employing lazy evaluation; calculating results immediately, rather than deferring calculation until they are required.

Examples:

"an eager algorithm"

Perfervid as an adjective:

Extremely, excessively, or feverishly passionate; zealous.