The most common and most likely answer to this crossword clue is the 9 letter word ETERNALLY
I've seen this crossword clue in The Guardian
E
T
E
R
N
A
L
L
Y
More clues leading to the result ETERNALLY
- Always near telly, unfortunately
- Stop daughter leaving new partner for good
- English bird, friend for ever
- Ultimately dependable teammate behind winger always
- Nearly let loose for ever
- English flier – a friend for ever
- Oriental that’s abandoned as partner for ever
- Nearly let off for all time
- Missing introduction, discourage new friend forever
- Outside times lost for ever
Buddy explains!

The straight part
We know that "for ever" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case for ever = eternally.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 ETERNALLY mean?
ETERNALLY adverb- For eternity; forever.
- Unceasingly, recurringly.