The most common and most likely answer to this crossword clue is the 7 letter word WINNING
I've seen this crossword clue in The Daily Telegraph
W
I
N
N
I
N
G
Buddy explains!

The straight part
We know that "Appealing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case appealing = winning.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 WINNING mean?
WINNING verb- To conquer, defeat.
- To reach some destination or object, despite difficulty or toil (now usually intransitive, with preposition or locative adverb).
- To triumph or achieve victory in (a game, a war, etc.).
- To gain (a prize) by succeeding in competition or contest.
- To obtain (someone) by wooing; to make an ally or friend of (frequently with over).
- To achieve victory.
- To have power, coercion or control.
- To obtain (something desired).
- To cause a victory for someone.
- To extract (ore, coal, etc.).
- The act of obtaining something, as in a contest or by competition.
- (chiefly in the plural) The money, etc., gained by success in competition or contest, especially in gambling.
- A new opening.
- The portion of a coalfield out for working.
- That constitutes a win.
- That leads to success.
- Attractive.