Stupid request almost entirely hollow (6)
I believe the answer is:
dimple
'hollow' is the definition.
(I've seen this before)
'stupid request almost entirely' is the wordplay.
'stupid' becomes 'dim' (similar in meaning).
'request' becomes 'plea' (plea is a kind of request).
'almost entirely' means to remove the last letter (most but not all of the word).
'plea' with its last letter removed is 'ple'.
'dim'+'ple'='DIMPLE'
(Other definitions for dimple that I've seen before include "Small hollow in cheek or chin" , "Fleshy dent" , "Small depression (in skin)" , "Attractive indentation in face" , "Facial depression" .)