The most common and most likely answer to this crossword clue is the 5 letter word ENVOI
I've seen this crossword clue in The Times
E
N
V
O
I
More clues leading to the result ENVOI
- Brief verse in French mostly useless
- Not all there, when voicing final words
- Last words of unfinished novel I destroyed
- One individual upset about verse and conclusion to verse
- Parting words starting barely halfway through drunken voicemail
- A lot of jealousy over one’s final words
- Final stanza that may be read in broken voice
- Conclusion of verse, that verse penned by number one
- Author’s last words, delivered with leaden voice
- Novice upset about missing conclusion
Buddy explains!

The straight part
We know that "Last words" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case last words = envoi.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 ENVOI mean?
ENVOI noun- A short stanza at the end of a poem, used either to address a person or to comment on the preceding body of the poem.