What is the antonym of feverishly?

There isn't one single perfect antonym for "feverishly". It depends on the context and what aspect of "feverishly" you want to contrast. Here are some possibilities:

For "intensely" or "with great energy":

* Calmly

* Leisurely

* Slowly

* Tranquilly

* Deliberately

* Methodically

For "excitedly" or "with great eagerness":

* Indifferently

* Apathetically

* Dispassionately

* Calmly

* Reluctantly

For "urgently" or "with haste":

* Slowly

* Patiently

* Calmly

* Deliberately

For "frantically" or "with agitation":

* Calmly

* Peacefully

* Serenely

* Composedly

The best antonym will depend on the specific situation.