Questions note accepting union member (5)
I believe the answer is:
pumps
'questions' is the definition.
(pumping is a kind of questioning)
'note accepting union member' is the wordplay.
'note' becomes 'ps' (PS is an example**).
'accepting' means one lot of letters goes inside another.
'union' becomes 'u' (common abbreviation as in 'Trades Union Congress').
'member' becomes 'mp'.
'u'+'mp'='ump'
'ps' going around 'ump' is 'PUMPS'.
(Other definitions for pumps that I've seen before include "Mechanical devices that move fluid or gas" , "Cycle attachments" , "Questions persistently; light shoes" , "Plimsolls" , "footwear" .)