bitterly [ˈbɪtəlɪ]
adverb
1 (icily)
it's bitterly cold hace un frío gélido glacial;or a bitterly cold day un día gélido glacial;or
2 (fiercely) [+oppose] implacablemente; [+hate] implacablemente; a muerte; [+fight] a muerte; [+criticize] duramente
a bitterly contested match un partido muy reñido
3 (deeply) [+regret, resent] amargamente; [+resentful, jealous, ashamed] terriblemente
I was bitterly disappointed sufrí una terrible amarga decepción;or quedé terriblemente decepcionado
