This is not even culture! (4)
I believe the answer is:
clue
'this' is the definition.
(the clue referring to itself!)
'not even culture' is the wordplay.
'not even' indicates alternate letters (remove even-numbered letters).
The alternate letters of 'culture' are 'CLUE'.
'is' acts as a link.
(Other definitions for clue that I've seen before include "Hint towards solution" , "Crossword hint?" , "It's here top be solved" , "contribution to crossword" , "Hint; piece of evidence" .)