The most common and most likely answer to this crossword clue is the 11 letter word SLIPSTREAMS
I've seen this crossword clue in The Daily Telegraph
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Buddy explains!
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 SLIPSTREAMS mean?
SLIPSTREAMS noun- The low-pressure zone immediately following a rapidly moving object, caused by turbulence.
- A genre of fantastic or non-realistic fiction that crosses conventional genre boundaries.
- To take advantage of the suction produced by a slipstream by travelling immediately behind the slipstream generator.
- To incorporate additional software (such as patches) into an existing installer.