The most common and most likely answer to this crossword clue is the 8 letter word LENITIVE
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The straight part
We know that "pain remedy" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case pain remedy = lenitive.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 LENITIVE mean?
LENITIVE noun- An analgesic or other source of relief from pain
- A laxative.
- Analgesic, able to reduce pain or suffering.
- Laxative; easing the bowels.
- (of a person) Mild; gentle.