Thoreau so moved, taking in grand country (5,5)
I believe the answer is:
south korea
'country' is the definition.
(I know that South Korea is a country)
'thoreau so moved taking in grand' is the wordplay.
'moved' indicates anagramming the letters.
'taking in' indicates putting letters inside.
'grand' becomes 'k' (both can mean a thousand pounds or dollars).
'thoreau'+'so'='thoreauso'
'thoreauso' with letters rearranged gives 'southorea'.
'southorea' enclosing 'k' is 'SOUTH KOREA'.
(Another definition for south korea that I've seen is " Country with capital Seoul".)