The most common and most likely answer to this crossword clue is the 10 letter word STEPFATHER
I've seen this crossword clue in The Daily Telegraph
S
T
E
P
F
A
T
H
E
R
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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 STEPFATHER mean?
STEPFATHER noun- The husband of one's biological mother, other than one's biological father, especially following the divorce or death of the father.