The most common and most likely answer to this crossword clue is the 11 letter word PENULTIMATE
I've seen this crossword clue in The Times
P
E
N
U
L
T
I
M
A
T
E
More clues leading to the result PENULTIMATE
Buddy explains!

The straight part
We know that "A" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a = penultimate.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 PENULTIMATE mean?
PENULTIMATE noun- A penult, a next-to-last thing, particularly:
- (in United States usually formal) Next to last, second to last; immediately preceding the end of a sequence, list, etc.
- Of or pertaining to a penult.
- Relating to or denoting an element of a related collection of curves that is arbitrarily close to a degenerate form.