The most common and most likely answer to this crossword clue is the 10 letter word ENLIGHTENS
I've seen this crossword clue in Financial Times
E
N
L
I
G
H
T
E
N
S
Buddy explains!

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 ENLIGHTENS mean?
ENLIGHTENS verb- To supply with light.
- To make something clear to (someone); to give knowledge or understanding to.