The phrase bad blood, often used to describe a bitter or hostile relationship between two people, can be substituted with a variety of synonyms. Some alternatives include animosity, enmity, hostility, antipathy, conflict, feud, resentment, bitterness, grudge, or acrimony. Each of these words implies a negative or unpleasant relationship between two or more individuals. For example, animosity suggests strong dislike or hostility, whereas resentment implies a lingering bitterness or indignation. No matter the word used, the underlying meaning remains the same: a deep-seated conflict or dislike that is typically difficult to resolve.