Dip in evacuation site, not to be annoying (4)
I believe the answer is:
dunk
'dip' is the definition.
(I know that dip can be written as dunk)
'evacuation site not to be annoying' is the wordplay.
I cannot really see how this works, but
'not' could be 'un' (prefix meaning 'not') and 'un' is found within the answer.
This explanation may well be incorrect...
'in' is the link.
(Other definitions for dunk that I've seen before include "Immerse (a biscuit)" , "Put into a liquid" , "Dip (eg, biscuit) in drink" , "Dip into tea, say" , "Dip (morsel) in liquid" .)