The most common and most likely answer to this crossword clue is the 6 letter word LAMENT
I've seen this crossword clue in Financial Times
L
A
M
E
N
T
More clues leading to the result LAMENT
- Regret being disabled, not losing heart
- The last word in Lieutenants threnody
- Bemoan lieutenant having the last word inside
- Blokes in US city originally translating funeral song
- Express disappointment over feeble set of books
- To Shakespeare’s readers mean imperfect collection of texts
- Moan about feeble National Trust
- A million involved in fast must be keen
- An air of sorrow?
- Mourn return of sickness, not short
Buddy explains!

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 LAMENT mean?
LAMENT noun- An expression of grief, suffering, sadness or regret.
- A song expressing grief.
- To express grief; to weep or wail; to mourn.
- To feel great sorrow or regret; to bewail.