The most common and most likely answer to this crossword clue is the 9 plus 3 letter word SATELLITE (+)
I've seen this crossword clue in The Guardian
S
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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 SATELLITE (+) mean?
SATELLITE (+) noun- A moon or other smaller body orbiting a larger one.
- A man-made apparatus designed to be placed in orbit around a celestial body, generally to relay information, data etc. to Earth.
- A country, state, office, building etc. which is under the jurisdiction, influence, or domination of another body.
- An attendant on an important person; a member of someone's retinue, often in a somewhat derogatory sense; a henchman.
- Satellite TV; reception of television broadcasts via services that utilize man-made satellite technology.
- (grammar) A grammatical construct that takes various forms and may encode a path of movement, a change of state, or the grammatical aspect. Examples: "a bird flew past"; "she turned on the light".
- To transmit by satellite.