Workforce on a Hebridean island (6)
I believe the answer is:
staffa
'hebridean island' is the definition.
(I've seen this before)
'workforce on a' is the wordplay.
'workforce' becomes 'staff' (I've seen this before).
'on' means one lot of letters go next to another.
'staff'+'a'='STAFFA'
(Other definitions for staffa that I've seen before include "Island west of Mull" , "Fingal's cave isle" , "Hebridean isle" , "small uninhabited island" , "northern isle" .)