Regularly engages clutch (4)
I believe the answer is:
eggs
'clutch' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
'regularly engages' is the wordplay.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
The alternate letters of 'engages' are 'EGGS'.
Can you help me to learn more?
(Other definitions for eggs that I've seen before include "Reproductive bodies" , "Poultry products" , "Don't teach your grandmother to suck --" , "Ova" , "Reproductive parts" .)