Emily Dickinson Lexicon

bitter (-er, -est), adj. [OE biter > bitan, bite.] (webplay: cold, cruel, day, keenness, sharp).

1. Unpleasant; grievous; painful; unpalatable to the mind; hard to accept; difficult to bear (see Exodus 1:14).
2. Strong; severe; extreme; sharp; cutting; polar; bitingly frigid; intensely cold.