The most common and most likely answer to this crossword clue is the 4 letter word ONLY
I've seen this crossword clue in Independent
O
N
L
Y
More clues leading to the result ONLY
- Sole aplenty, reel in two, all tails up
- Just over 50 in US city
- Sole Liberal accommodated in old city
- Just on left, close to lay-by
- Just about to have lavatory emptied
- Sole Liberal in west end of Oklahoma City
- Exclusively working with vergers in Ledbury
- Just about? Extremely likely!
- No more than 9 making independent navy
- Regularly downplays exclusive
Buddy explains!

The straight part
We know that "No more than" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case no more than = only.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 ONLY mean?
ONLY noun- An only child.
- Alone in a category.
- Singularly superior; the best.
- Without sibling; without a sibling of the same gender.
- Mere.
- Without others or anything further; exclusively.
- No more than; just.
- As recently as.
- Used to express surprise or consternation at an action.
- Introduces a disappointing or surprising outcome that renders futile something previously mentioned. See also only to, only for.
- Above all others; particularly.
- Under the condition that; but.
- But; except.