bitterly
1. [ adverb ] in a resentful manner
Synonyms: with_bitterness
Examples:

"she complained bitterly"

Related terms: acrimonious acrimonious
2. [ adverb ] indicating something hard to accept
Examples:

"he was bitterly disappointed"

Related terms: bitter bitter
3. [ adverb ] extremely and sharply
Synonyms: bitingly bitter piercingly
Examples:

"it was bitterly cold" "bitter cold"

Related terms: cutting biting biting biting