Maybe Swede’s boss informally embracing celebrity, mostly (6)
I believe the answer is:
gustav
'maybe swede's' is the definition.
I can't judge whether this definition defines the answer.
'boss informally embracing celebrity mostly' is the wordplay.
'boss informally' becomes 'guv' (I can't justify this - if you can you should give a lot more credence to this answer).
'embracing' means one lot of letters goes inside another.
'celebrity' becomes 'star' (I've seen this before).
'mostly' means to remove the last letter.
'star' with its last letter removed is 'sta'.
'guv' going around 'sta' is 'GUSTAV'.
Can you help me to learn more?
(Other definitions for gustav that I've seen before include "- Holst, Eng. composer" , "Swedish king" , "-- Mahler, symphonist" , "Perhaps Hertz" , "... Mahler (composer)" .)