insanely
in-sane-ly
adverb
To an extreme or remarkable degree; very much so.
"The queue for the concert was insanely long."
adverb
In a manner characteristic of a mad or irrational person.
"He was behaving insanely after the shocking news."
Thesaurus
Synonyms: dementedly, madly, crazily, devilishly, deucedly, deadly
Antonyms: sanely