The most common and most likely answer to this crossword clue is the 8 letter word CANTICLE
I've seen this crossword clue in The Daily Telegraph
C
A
N
T
I
C
L
E
More clues leading to the result CANTICLE
- Hymn may be amusing when king is deposed
- Lack cake decorating skills when receiving large number of churchgoers
- . Song is able to delight passing king
- Hymn in vernacular Latin kept in reserve
- Hymn is horrible — cancel it
- Chant from choir, originally in Latin, modified in church
- This may be said about a strange client
- Song may amuse if heard on the radio
- Non-metrical hymn may amuse, we hear
- Song of songs able to amuse when heard
Buddy explains!

The straight part
We know that "Song" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case song = canticle.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 CANTICLE mean?
CANTICLE noun- A chant, hymn or song, especially a nonmetrical one, with words from a biblical text.