The most common and most likely answer to this crossword clue is the 11 letter word CLANDESTINE
I've seen this crossword clue in The Times
C
L
A
N
D
E
S
T
I
N
E
More clues leading to the result CLANDESTINE
- Secret tribe doomed to come to premature end
- Secret in family meant stopping short
- Family all but condemned in secret
- Group meeting fate underground
- Secret group bound to be reduced
- . Cameron, perhaps fated to spill daughter’s secret
- Enigmatic client secures chain, being private
- Almost doomed by family secret
- Wound isn’t cleaned in private
- Private dance, silent, moving
Buddy explains!
The straight part
We know that "in secret" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case in secret = clandestine.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 CLANDESTINE mean?
CLANDESTINE adjective- Done or kept in secret, sometimes to conceal an illicit or improper purpose.
- (of a person or lodge) Not recognized as a regular member.