Male, working, observed to be well-off (7)
I believe the answer is:
moneyed
'be well-off' is the definition.
(I've seen this in another clue)
'male working observed' is the wordplay.
'male' becomes 'm' (common abbreviation).
'working' becomes 'on' (on can mean working or activated).
'observed' becomes 'eyed' (I've seen this before).
'm'+'on'+'eyed'='MONEYED'
'to' acts as a link.
(Other definitions for moneyed that I've seen before include "Having means" , "Mo' needy? (Anag)" , "Well-off" , "flush" , "rolling in it" .)