21 down
Run
over
manuscript
for
secluded
groups
(6)
Run over manuscript for secluded groups (6)
hints
0
checks
0
hints
The definition is at the end of the clue.
How the clue works
See secluded groups there at the end — that's your definition, pointing to harems. For the wordplay, take HARE (to run, like the animal does, or "to run swiftly") and sit it over MS (the usual abbreviation for manuscript), giving you HAREMS.