The most common and most likely answer to this crossword clue is the 10 letter word CROSSCHECK
I've seen this crossword clue in The Daily Telegraph
C
R
O
S
S
C
H
E
C
K
More clues leading to the result CROSSCHECK
Buddy explains!

The straight part
We know that "Verify" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case verify = crosscheck.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 CROSSCHECK mean?
CROSSCHECK noun- A penalty where a player strikes another with the shaft of his stick.
- A penalty where a player hits another player with the shaft of their lacrosse stick with their hands spread apart.
- To hit another player with the shaft of a lacrosse stick.
- To re-examine; to double-check.