The most common and most likely answer to this crossword clue is the 9 letter word THANKLESS
I've seen this crossword clue in The Guardian
T
H
A
N
K
L
E
S
S
More clues leading to the result THANKLESS
- Unrewarding time without Marvin?
- In sh*t, rolled joints, getting no appreciation
- Hot joints in westward street unappreciated
- No gratitude shown by extremely tough joints over Sunday opening
- When King & Lewis electrified segregated Selma, initially lacking appreciation
- Running through with ankles shackled is unrewarding
Buddy explains!

The straight part
We know that "getting no appreciation" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case getting no appreciation = thankless.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 THANKLESS mean?
THANKLESS adjective- (of a task) not appreciated or rewarded
- (of a person) ungrateful or unappreciative