Eg Marilyn Monroe’s heavenly body? (4)
I believe the answer is:
star
I believe this clue is a double definition.
'eg marilyn monroe's' is the first definition.
(Marilyn Monroe is an example of a star)
'heavenly body?' is the second definition.
(star is a kind of heavenly body)
(Other definitions for star that I've seen before include "Celebrated performer" , "top player" , "Famous entertainer" , "Symbol of excellence" , "Glamorous celebrity" .)