Ever so bothered about Britain, say (7)
I believe the answer is:
observe
'say' is the definition.
(observing is a kind of saying)
'ever so bothered about britain' is the wordplay.
'bothered' is an anagram indicator.
'about' means one lot of letters goes inside another.
'britain' becomes 'b' (common abbreviation as in GB).
'ever'+'so'='everso'
'everso' with letters rearranged gives 'oserve'.
'oserve' going around 'b' is 'OBSERVE'.
(Other definitions for observe that I've seen before include "Witness, watch" , "Keep; notice" , "Notice, perceive" , "Notice or conform to, rules say" , "taking notice" .)