The most common and most likely answer to this crossword clue is the 5 letter word SPITE
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The straight part
We know that "resentment" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case resentment = spite.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SPITE mean?
SPITE noun- Ill will or hatred toward another, accompanied with the desire to irritate, annoy, or thwart; a want to disturb or put out another; mild malice
- Vexation; chagrin; mortification.
- To treat maliciously; to try to injure or thwart.
- To be angry at; to hate.
- To fill with spite; to offend; to vex.
- Notwithstanding; despite.