The most common and most likely answer to this crossword clue is the 2 plus 2 plus 1 plus 5 letter word UP TO A POINT
I've seen this crossword clue in The Guardian
U
P
T
O
A
P
O
I
N
T
More clues leading to the result UP TO A POINT
- Opt out with pain, suffering to some extent
- A pout developed with purpose? Not wholly
- Fluid put on patio? Not altogether
- Partly ready with a job offer, we hear
- Not altogether how pyramids are built
- Partly capable of having some beer, getting round in
- After university, Ian dabbled with pot twice, moderately
- Somewhat resembling how the Burj Khalifa was constructed?
Buddy explains!

The straight part
We know that "Not altogether" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case not altogether = up to a point.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.