Mother unhappy about the name on the cover of a magazine? (8)
I believe the answer is:
masthead
'name on the cover of a magazine?' is the definition.
(part of a magazine cover displaying its name)
'mother unhappy about the' is the wordplay.
'mother' becomes 'ma' (Ma is another word for mother or mum).
'unhappy' becomes 'sad' (synonyms).
'about' indicates putting letters inside.
'sad' placed around 'the' is 'sthead'.
'ma'+'sthead'='MASTHEAD'
(Other definitions for masthead that I've seen before include "Newspaper identity" , "Telegraph, perhaps" , "on newspaper cover" , "Big name appears here" , "Something in large type" .)