"Beauty is truth, truth beauty" poet
I believe the answer is:
keats
'beauty is truth truth beauty poet' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for keats that I've seen before include "To a Nightingale poet" , "Early 19th century poet" , "English odist" , "English poet, 1795-1821" , "English romantic poet, d. 1821" .)