The most common and most likely answer to this crossword clue is the 5 plus 4 letter word LIGHT YEAR
I've seen this crossword clue in The Guardian
L
I
G
H
T
Y
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A
R
More clues leading to the result LIGHT YEAR
- Finally Plymouth Argyle - it's awfully far to go!
- Land you found north of a river in the distance
- A girl they treated for what isn’t really a long time
- Extraordinary way gay Hitler minced
- Great distance I travelled with lethargy
- Land on time from long distance
- A long way in a short time?
- Leader of infantry overcome by lethargy, getting mobile unit
- A girl they fancy that is way beyond anyone’s reach!
- A long way from home for soldiers, heading off to eastern Arabia
Buddy explains!
The straight part
We know that "Great distance" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case great distance = light year.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 LIGHT YEAR mean?
LIGHT YEAR noun- A unit of length (abbreviation ly; equal to just under 10 trillion kilometres (1016 metres)) equal to the distance light travels in one Julian year; used to measure extremely large distances.
- (only in plural) A very long way.
- (only in plural) A very long time.