Singer that gets high, really a negative where publicity is involved (7)
I believe the answer is:
soprano
'singer that gets high' is the definition.
'soprano' can be an answer for 'singer' (type of singing voice). I'm unsure of the remainder of the definition.
'really a negative where publicity is involved' is the wordplay.
'really' becomes 'so' (both can mean 'extremely').
'negative where' becomes 'no' (no is a kind of negative. I am not sure about the 'where' bit.).
'publicity' becomes 'PR' (abbreviation for public relations).
'is involved' means one lot of letters goes inside another.
'so'+'a'+'no'='soano'
'soano' going around 'pr' is 'SOPRANO'.
Can you help me to learn more?
(Other definitions for soprano that I've seen before include "Woman singing" , "High female voice" , "gangster" , "Sutherland?" , "chorus girl, perhaps" .)