A couple regularly query lay (7)
I believe the answer is:
amateur
'lay' is the definition.
(as in a layman)
'a couple regularly query' is the wordplay.
'couple' becomes 'mate' (synonyms).
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
The alternating letters of 'query' are 'ur'.
'a'+'mate'+'ur'='AMATEUR'
(Other definitions for amateur that I've seen before include "Unpaid performer" , "Inept, non-professional" , "I'm no expert!" , "lacking professionalism" , "Athlete who performs without payment" .)