Peg rings regularly in place (6)
I believe the answer is:
spigot
'peg' is the definition.
(I've seen this before)
'rings regularly in place' is the wordplay.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
'in' indicates putting letters inside.
'place' becomes 'spot' ('spot' can be a synonym of 'place'**).
The alternate letters of 'rings' are 'ig'.
'ig' going into 'spot' is 'SPIGOT'.
(Other definitions for spigot that I've seen before include "Plug - an American tap" , "It's a water tap in America" , "Cask stopper" , "Got sip? (Anag)" , "Tap fitted to a cask" .)