Ineffectual people shun cue, stupidly (7)
I believe the answer is:
eunuchs
'ineffectual people' is the definition.
(I've seen this before)
'shun cue stupidly' is the wordplay.
'stupidly' indicates an anagram (a stupid ordering of the letters).
'shun'+'cue'='shuncue'
'shuncue' is an anagram of 'EUNUCHS'.
(Other definitions for eunuchs that I've seen before include "Harem guards" , "deprived men" , "Men cut out for work in harems?" , "Harem attendants" , "Castrati" .)