The most common and most likely answer to this crossword clue is the 11 letter word THERAPEUTIC
I've seen this crossword clue in The Sunday Telegraph
T
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More clues leading to the result THERAPEUTIC
Buddy explains!
The straight part
We know that "Remedial" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case remedial = therapeutic.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 THERAPEUTIC mean?
THERAPEUTIC noun- A therapeutic agent
- Of, or relating to therapy.
- Having a positive effect on the body or mind.