Regattas regularly providing food (4)
I believe the answer is:
eats
'food' is the definition.
(eats is a kind of food)
'regattas regularly' is the wordplay.
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
The alternating letters of 'regattas' are 'EATS'.
'providing' acts as a link.
(Other definitions for eats that I've seen before include "Devours - food" , "Takes meals" , "Gets tucked into the cake" , "what is on the Christmas menu" , "Scoffs" .)