bitter

Compared meaning: hostile feelings caused by anger (adjective).

比较义项：因感到愤怒、怨恨而产生的敌意情绪（形容词）。

• bitter 本词

  Describes a person's long-lasting feeling of anger and resentment, often about general disappointment or unfair treatment over time; neutral register, and can also literally mean having a sharp, unpleasant taste (not the sense compared here).

  该词形容人长期怀有的愤怒怨恨情绪，通常源于长期的失望或不公；语域中性。bitter还有“味道苦涩”的本义，此处不作比较。

  Years of bad luck had left him bitter and quick to complain.

  多年的厄运让他变得满心怨恨，动不动就抱怨。

• resentful

  Describes anger caused specifically by a sense of being treated unfairly, usually pointed at a particular person or event; more targeted than the general bitterness of 'bitter'.

  该词专指因觉得受到不公对待而产生的愤怒，通常针对某个具体的人或事件，比bitter更具针对性。

  She grew resentful when her coworker got the promotion she deserved.

  当同事得到了本该属于她的晋升时，她心生怨恨。

• acrimonious

  Describes disputes, negotiations, or relationships marked by open anger and harsh words, not a person's inner feeling; typically modifies things like arguments, meetings, or divorces, not people.

  该词形容争论、谈判或关系中表现出的公开愤怒与尖刻言辞，而非人的内心感受；通常修饰争吵、会议、离婚等，而不是人本身。

  The custody battle grew increasingly acrimonious, with both parents trading insults in court.

  这场监护权争夺战愈发激烈，双方父母在法庭上互相辱骂。

Bitter, resentful, and acrimonious all describe hostility caused by anger. Bitter describes a person's long-lasting resentment, often about unfair treatment over time. Resentful is anger aimed at a specific person or event felt as unfair. Acrimonious describes disputes or relationships, not people, marked by anger.

这三个词都可表示因愤怒而生的怨恨情绪，但侧重点不同：bitter和resentful多用来形容人内心长期或因不公而产生的怨恨感受，acrimonious则多用来形容争论、谈判或关系中公开表现出的尖刻与敌意，而非直接形容人的内心感受。此处不比较bitter“味道苦涩”这一本义。