The most common and most likely answer to this crossword clue is the 8 letter word CHORALLY
C
H
O
R
A
L
L
Y
More clues leading to the result CHORALLY
Buddy explains!
The straight part
We know that "How 4 may be rendered" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case how 4 may be rendered = chorally.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.