Dog eating nothing for tea (5)
I believe the answer is:
pekoe
'for tea' is the definition.
(pekoe is a kind of tea)
'dog eating nothing' is the wordplay.
'dog' becomes 'peke' (short for Pekingese).
'eating' indicates putting letters inside.
'nothing' becomes 'O' (O resembles 0).
'peke' placed around 'o' is 'PEKOE'.
(Other definitions for pekoe that I've seen before include "Scented black tea" , "Variety of black tea" , "Thin mark; run naked" , "Type of black tea" , "Superior grade of black tea" .)