The most common and most likely answer to this crossword clue is the 8 letter word SECRETED
S
E
C
R
E
T
E
D
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The straight part
We know that "Sent out" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sent out = secreted.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 SECRETED mean?
SECRETED verb- To make or keep secret.
- To hide secretly.
- (of organs, glands, etc.) To extract a substance from blood, sap, or similar to produce and emit waste for excretion or for the fulfilling of a physiological function.
- To exude or yield.
- To conceal.