Curious revolutionary poet's last letters (4)
I believe the answer is:
nosy
'curious' is the definition.
(similar in meaning)
'revolutionary poet's last letters' is the wordplay.
'revolutionary' says the letters should be written backwards.
'poet' becomes 'tennyson' (Alfred, Lord Tennyson).
'last letters' indicates taking half (only the second half of letters used).
'tennyson' halved is 'yson'.
'yson' back-to-front is 'NOSY'.
(Other definitions for nosy that I've seen before include "Offensively curious or inquisitive" , "Prying, snoopy" , "Meddlesome" , "Fragrant" , "lots of questions" .)