The most common and most likely answer to this crossword clue is the 12 letter word INTERSTELLAR
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More clues leading to the result INTERSTELLAR
- Command to infiltrate alien terrains in the realm of Star Trek
- Lost all interest with the onset of rows between stars
- Seconds count in unfamiliar terrain, among the stars
- From pointers tell a relationship between stars
- In printer’s, tell arbitrarily between Sun and Star?
- Trailers lent out between stars
- Among the stars, playwright heading off right behind McCartney?
Buddy explains!

The straight part
We know that "between Sun and Star" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case between sun and star = interstellar.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 INTERSTELLAR mean?
INTERSTELLAR adjective- Between the stars.
- Among the stars.