The most common and most likely answer to this crossword clue is the 6 plus 4 letter word GROUND PLAN
I've seen this crossword clue in Financial Times
G
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More clues leading to the result GROUND PLAN
Buddy explains!
The straight part
We know that "it might represent 1, 15 down" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it might represent 1, 15 down = ground plan.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 GROUND PLAN mean?
GROUND PLAN noun- A diagram showing the physical layout of a set, especially the placement of structures on the stage, as opposed to items on the walls or suspended from the ceiling.
- A diagram, usually to scale, showing the layout of the ground level of a building or other physical structure; floorplan.
- A framework or pattern showing the form of something, without all the details.
- A hypothetical anatomical form from which members of a clade are adaptations.