noun
rancor
RANG-ker/ˈræŋkər/
Deep-seated bitterness or hostility.
The estranged adults exchange bitter looks filled with rancor.

Etymology
Latin rancor named both a stinking smell and a bitter grudge. The emotional meaning transfers the unpleasantness of rancidness to deeply felt resentment.
In context
they see them as bad people whose ways of thinking are dangerous or incomprehensible they see them as enemies this level of rancor and mistrust
More examples
- Years later, rancor still divides the two families.
- They settle their disagreement without rancor.
- His apology does little to ease the rancor between them.
Forms
rancor
rancorous adjective — Showing deep bitterness or lasting hostility.
Similar words
- resentment
- Emphasizes bitterness about unfair treatment, not necessarily deep hostility.
- hostility
- Focuses on antagonism or opposition rather than lingering bitterness.
- bitterness
- Can describe disappointment or hurt without hostility toward someone.