The most common and most likely answer to this crossword clue is the 5 plus 2 plus 3 plus 4 letter word BROAD IN THE BEAM
I've seen this crossword clue in Independent
B
R
O
A
D
I
N
T
H
E
B
E
A
M
Buddy explains!
The straight part
We know that "wide" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wide = broad in the beam.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.