The most common and most likely answer to this crossword clue is the 4 plus 3 plus 6 letter word FAIR AND SQUARE
I've seen this crossword clue in The Sunday Telegraph
F
A
I
R
A
N
D
S
Q
U
A
R
E
More clues leading to the result FAIR AND SQUARE
- Conservative after market also honest
- Not cheating like a blonde conservative?
- Fellow, with help, managed to come in and settle up honestly
- Honest thus to describe old-fashioned blonde?
- How you might describe an old-fashioned looker, honestly
- Nation in fashion, conventional honestly
- Completely honest followers of Scarborough and Leicester
- Honest description of old-fashioned blonde?
- Figure after fashion defending country honestly
- Character in cool gamble captures spade queen legitimately
Buddy explains!

The straight part
We know that "honestly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case honestly = fair and square.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.