Group in silence gathered round north (4)
I believe the answer is:
gang
'group' is the definition.
(a gang is a group of people)
'silence gathered round north' is the wordplay.
'silence' becomes 'gag' (gagging is a kind of silencing).
'gathered round' indicates putting letters inside.
'north' becomes 'N' (abbreviation).
'gag' enclosing 'n' is 'GANG'.
'in' is the link.
(Other definitions for gang that I've seen before include "Organized group of workmen" , "Work, criminal, group" , "Working group or mob of hoodlums" , "Group (crazy or criminal?)" , "Association of criminals" .)