IPA: /ˈbɪtərli/
KK: /ˈbɪtərli/
In a way that shows strong feelings of sadness, anger, or disappointment.
She bitterly regretted her decision to leave the job.
Bitterly → It is formed from "bitter" (from Old English "biter", meaning having a sharp taste or unpleasant flavor) and "-ly" (a suffix used to form adverbs). The word "bitterly" means in a manner that is sharp or unpleasant, often used to describe feelings or expressions of deep sadness or resentment.
Think of the word 'bitter' to remember that 'bitterly' describes something done in a sharp or unpleasant way, often related to strong emotions.