Placement of flyers plugging trendy joint (10)
I believe the answer is:
internship
'placement' is the definition.
(internship is a type of placement or work position)
'flyers plugging trendy joint' is the wordplay.
'flyers' becomes 'terns' (tern is a type of bird).
'plugging' is an insertion indicator (I've seen this in other clues).
'trendy' becomes 'in' ('in' can mean fashionable).
'joint' becomes 'hip' (part of body).
'in'+'hip'='inhip'
'terns' placed inside 'inhip' is 'INTERNSHIP'.
'of' is the link.
(Other definitions for internship that I've seen before include "practical training programme" , "being a trainee?" , "Work experience position" , "Trainee's spell" .)