Definitions

1. adverb

in a way that is extremely difficult or unpleasant to endure or bear; to an unbearable degree

“The heat was unbearable, and it was being felt unbearably as the sun beat down.”

2. adverb

in a manner that is extremely unpleasant or difficult to tolerate; in a way that causes great discomfort or pain

“She was feeling unbearably sad after the breakup.”