Work comes up, varies regularly (6)
I believe the answer is:
oeuvre
'work' is the definition.
(an oeuvre is someone's collected works)
'comes up varies regularly' is the wordplay.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
'comes'+'up'+'varies'='comesupvaries'
The alternating letters of 'comesupvaries' are 'OEUVRE'.
(Other definitions for oeuvre that I've seen before include "Complete works (Fr.)" , "Substantial body of work from our Eve" , "A lifetime's body of work" , "All one's writings" , "Collected works" .)