Master satisfied to retire for the present (3,3)
I believe the answer is:
pro tem
'for the present' is the definition.
(I've seen this before)
'master satisfied to retire' is the wordplay.
'master' becomes 'pro' (both can mean an expert).
'satisfied' becomes 'met' (as in 'met the conditions of his contract').
'to retire' says the letters should be written in reverse (retire can mean to go back).
'met' written backwards gives 'tem'.
'pro'+'tem'='PRO TEM'
(Other definitions for pro tem that I've seen before include "For the time being, to the old Romans in short" , "'For the time being (3,3)'" , "Informally, for the time being" , "until proper arrangement is made" , "For the time being (Latin abbreviation)" .)