Unwelcome intrusion (8)
I believe the answer is:
invasion
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">unwelcome intrusion</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for invasion that I've seen before include "Occupation" , "Encroachment by an army" , "Unwelcome encroachment on another country" , "Hostile incursion" , "Unwelcome intrusion" .)