The most common and most likely answer to this crossword clue is the 13 letter word COMPASSIONATE
I've seen this crossword clue in The Times
C
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M
P
A
S
S
I
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A
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Buddy explains!
The straight part
We know that "Sympathetic" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sympathetic = compassionate.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 COMPASSIONATE mean?
COMPASSIONATE verb- To feel compassion (for someone or with regard to something); to regard (someone or something) with compassion.
- Having, feeling or showing compassion (to or toward someone).
- Given to someone as an exception because of a family emergency or a death in their family.
- Inviting or asking for pity.