Country song keeping us tense (7)
I believe the answer is:
austria
'country' is the definition.
(Austria is an example)
'song keeping us tense' is the wordplay.
'song' becomes 'aria' (aria is a kind of song).
'keeping' means one lot of letters goes inside another.
'tense' becomes 't' (abbreviation used in many dictionaries).
'us'+'t'='ust'
'aria' placed around 'ust' is 'AUSTRIA'.
(Other definitions for austria that I've seen before include "land in Europe" , "EU country" , "The capital is Vienna (7)" , "Mountainous European republic" , "The Von Trapps lived there" .)