Emily Dickinson Lexicon

BIT'TER-NESS, n. [from bitter.]

1. A bitter taste; or rather a quality in things which excites a biting disagreeable sensation in the tongue.
2. In a figurative sense, extreme enmity, grudge, hatred; or rather an excessive degree or implacableness of passions and emotions; as, the bitterness of anger. – Eph. iv.
3. Sharpness; severity of temper.
4. Keeness of reproach; piquancy; biting sarcasm.
5. Keen sorrow; painful affliction; vexation; deep distress of mind. Hannah was in bitterness of soul. – 1 Sam. i. Job vii. In the gall of bitterness, in a state of extreme impiety or enmity to God. – Acts viii. Root of bitterness, a dangerous error, or schism, tending to draw persons to apostasy. – Heb. xii.