Morning rest for the boss (6)
I believe the answer is:
master
'the boss' is the definition.
(I've seen this before)
'morning rest' is the wordplay.
I cannot quite see how this works, but
an anagram of 'rest' is 'ster' which is present in the answer.
The remaining letters 'ma' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'for' acts as a link.
Can you help me to learn more?
(Other definitions for master that I've seen before include "Male dog owner" , "Maestro; teacher" , "An old one is one of the early and great European painters" , "Expert" , "Strong chess player" .)