The most common and most likely answer to this crossword clue is the 10 letter word GUESTIMATE
I've seen this crossword clue in The Daily Telegraph
G
U
E
S
T
I
M
A
T
E
More clues leading to the result GUESTIMATE
- Judgement of visitor with current partner
- Invitee and one chum give a rough idea
- Roughly work out with patron I partner
- Visitor and partner must accept independent judge
- ‘Mr Smith’ staying at hotel with one ‘Mrs Smith’? The conjecture may be fair enough!
- Reasonable judgement shown by one keeping lodger and lover apart
Buddy explains!
The straight part
We know that "judge" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case judge = guestimate.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.
Crossword Answer definitions
GUESTIMATE noun- An estimate that is hardly any better than a guess, often because it is based on insufficient or unreliable data.
- To make a guesstimate.
- To make a guesstimate of a specific quantity.