Paid with radicchio, initially, that is found among mixed greens (8)
I believe the answer is:
salaried
'paid' is the definition.
(similar in meaning)
'radicchio initially that is found among mixed greens' is the wordplay.
'initially' says to take the initial letters.
'that is' becomes 'ie' (short for Latin 'id est', 'that is').
'found among' is an insertion indicator.
'mixed greens' becomes 'salad' (I've seen this in another clue).
The initial letter of 'radicchio' is 'r'.
'r'+'ie'='rie'
'rie' going into 'salad' is 'SALARIED'.
'with' is the link.
(Other definitions for salaried that I've seen before include "Paid monthly for work" , "Earning a living" , "Paid regularly" .)