The most common and most likely answer to this crossword clue is the 9 letter word PERPETUAL
I've seen this crossword clue in The Guardian
P
E
R
P
E
T
U
A
L
More clues leading to the result PERPETUAL
- A cat for one oddly unable to be immortal
- Everlasting ill repute acquired by mate
- It means endless trouble for Peter and Paul
- Persistent US criminal turned up dead outside university
- Constant favourite in nation, a leader in legend
- Incessant bell-ringing entertains favourite during game
- Endless scrutiny after thieves finally escape, stealing treasure
- Put a leper through treatment that’s going on for ever
Buddy explains!
The straight part
We know that "It means endless" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it means endless = perpetual.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 PERPETUAL mean?
PERPETUAL adjective- Lasting forever, or for an indefinitely long time
- Set up to be in effect or have tenure for an unlimited duration
- Continuing; uninterrupted
- Flowering throughout the growing season