Emily Dickinson Lexicon

IM-BIT'TER, v.t. [in and bitter.]

1. To make bitter.
2. To make unhappy or grievous; to render distressing. The sins of youth often imbitter old age. Grief imbitters our enjoyments.
3. To exasperate; to make more severe, poignant or painful. The sorrows of true penitence are imbittered by a sense of our ingratitude to our Almighty Benefactor.
4. To exasperate; to render more violent or malignant; as, to imbitter enmity, anger, rage, passion, &c.