Keep quiet about amateur artist's name (5)
I believe the answer is:
sarah
'name' is the definition.
'keep quiet about amateur artist's' is the wordplay.
'keep quiet' becomes 'sh'.
'about' means one lot of letters goes inside another.
'amateur' becomes 'a'.
'artist' becomes 'ra' (Royal Academician, member of Royal Academy of Arts).
'a'+'ra'='ara'
'sh' placed around 'ara' is 'SARAH'.
(Other definitions for sarah that I've seen before include "Abraham's wife in the Old Testament" , "Girl's name" , "- Bernhardt, Fr. actress" , "Girl" , "Woman" .)