Messily eat refreshment (3)
I believe the answer is:
tea
'refreshment' is the definition.
(I've seen this before)
'messily eat' is the wordplay.
'messily' indicates an anagram.
'eat' anagrammed gives 'TEA'.
(Other definitions for tea that I've seen before include "Brew" , "Plantation product" , "Lapsang souchong" , "Leaves for brewing" , "Earl Grey?" .)