Harry lost aide, getting separated (8)
I believe the answer is:
isolated
'separated' is the definition.
(I know that separated can be written as isolated)
'harry lost aide getting' is the wordplay.
'harry' indicates anagramming the letters (harry can mean to attack or spoil).
'getting' means one lot of letters go next to another.
'lost'+'aide'='lostaide'
'lostaide' is an anagram of 'ISOLATED'.
(Other definitions for isolated that I've seen before include "Quarantined, alone" , "Placed apart from others" , "individual" , "Idols ate (anag.)" , "Alone, apart, detached" .)