Light meal vampires have? (4)

I believe the answer is:

bite

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'light meal' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for bite that I've seen before include "Get teeth into" , "Nip; nibble" , "Small amount to eat" , "Quick snack" , "Take bait; sting" .)

I've seen this clue in The Sun.

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