The most common and most likely answer to this crossword clue is the 10 letter word TOW-HEADED
I've seen this crossword clue in Financial Times
T
O
W
-
H
E
A
D
E
D
Buddy explains!
The straight part
We know that "Blonde" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case blonde = tow-headed.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 TOW-HEADED mean?
TOW-HEADED adjective- Having pale blond hair, resembling tow.