Conservative is entertained by group of stars showing prejudice (6)
I believe the answer is:
racism
'prejudice' is the definition.
(I know that racism is a type of prejudice)
'conservative is entertained by group of stars' is the wordplay.
'conservative' becomes 'C' (UK political abbreviation).
'entertained by' indicates putting letters inside (inserted letters are hosted or entertained).
'group of stars' becomes 'ram' (I am not sure about this - if you are sure you should believe this answer much more).
'c'+'is'='cis'
'cis' put inside 'ram' is 'RACISM'.
'showing' acts as a link.
Can you help me to learn more?
(Other definitions for racism that I've seen before include "Prejudice against people of other countries or nationalities" , "Ethnic prejudice" , "Prejudice regarding ethnicity" , "Form of discrimination" , "Nazi-style discrimination" .)