Posh twin unsettled small community (8)
I believe the answer is:
township
'small community' is the definition.
(I've seen this before)
'posh twin unsettled' is the wordplay.
'unsettled' is an anagram indicator.
'posh'+'twin'='poshtwin'
'poshtwin' is an anagram of 'TOWNSHIP'.
(Other definitions for township that I've seen before include "Small community" , "Poor suburb (South Africa) - county division (US) - part of parish (England)" , "Municipality" , "In South Africa during apartheid, an urban area assigned to black nationals" , "Urban area for non-whites in South Africa under apartheid" .)