The most common and most likely answer to this crossword clue is the 8 plus 7 letter word VICTORIA CROSSES
I've seen this crossword clue in The Times
V
I
C
T
O
R
I
A
C
R
O
S
S
E
S
Buddy explains!
The straight part
We know that "medals" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case medals = victoria crosses.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.