The most common and most likely answer to this crossword clue is the 7 letter word TACHYON
I've seen this crossword clue in The Guardian
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More clues leading to the result TACHYON
- High-speed traveller in theory on yacht at sea
- After working on yacht, in principle it goes very fast
- No yacht could be something travelling faster than light
- Yacht on manoeuvres is one moving quickly
- No energy to instruct year about theoretical particle
- Painful to go through — not rejecting a hypothetical particle
Buddy explains!
The straight part
We know that "in principle it goes very fast" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case in principle it goes very fast = tachyon.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 TACHYON mean?
TACHYON noun- A hypothetical particle that travels faster than the speed of light.
- A flaw in a physical theory that predicts the existence of tachyons or similar paradoxical results. Compare with ghost.