Term of Liberal and then changes around Government (6)
I believe the answer is:
length
'term' is the definition.
(thesaurus)
'liberal and then changes around government' is the wordplay.
'liberal' becomes 'l' (abbreviation**).
'changes' is an anagram indicator.
'around' is an insertion indicator.
'government' becomes 'g'.
'then' is an anagram of 'enth'.
'enth' enclosing 'g' is 'ength'.
'l'+'ength'='LENGTH'
'of' acts as a link.
(Other definitions for length that I've seen before include "A bit of swimming" , "Linear dimension" , "Extent - distance" , "Extent from end to end" , "Duration, extent" .)