Afternoon meal taken in Hampstead (3)
I believe the answer is:
tea
'afternoon meal' is the definition.
(meal eaten in the afternoon)
'in hampstead' is the wordplay.
'in' indicates the answer is hidden within the clue.
'TEA' is hidden in the letters of 'hampstead'.
'taken' is the link.
(Other definitions for tea that I've seen before include "Early evening meal" , "For Japanese ceremony" , "Shrub; drink" , "Refreshment" , "Brew" .)