Still 0-0? (4)

I believe the answer is:

even

I'm a little stuck... Click here to teach me more about this clue!

'still' is the definition.
(synonyms)

I don't understand the remainder of the clue.

(Other definitions for even that I've seen before include "Smooth, level" , "Still - divisible by two" , "Flat, level" , "(Of a number) divisible by 2" , "Equable" .)

I've seen this clue in The Sun.

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