embittered

adj

1. Deeply hostile, resentful.

   “an embittered enemy”

   “[…] they were opposed to it on grounds that were at once legal, political, historical, personal, geographical, and mixed; the whole combination of causes operating of necessity to make the opposition an embittered one.”

   “Again, by means of the ‘follower’s’ life, it will be revealed who is the admirer; for the admirers will become highly embittered against the follower.”

   “Dawkins’ book is, oddly, much more embittered and deeply emotional, although leavened by his effervescent wit.”

verb

1. (form-of, participle, past)simple past and past participle of embitter