The most common and most likely answer to this crossword clue is the 8 letter word EMBOSSER
I've seen this crossword clue in The Times
E
M
B
O
S
S
E
R
More clues leading to the result EMBOSSER
Buddy explains!

The straight part
We know that "One providing relief" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one providing relief = embosser.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.