The most common and most likely answer to this crossword clue is the 7 plus 6 letter word MATTHEW ARNOLD
I've seen this crossword clue in The Guardian
M
A
T
T
H
E
W
A
R
N
O
L
D
More clues leading to the result MATTHEW ARNOLD
Buddy explains!
The straight part
We know that "Poet" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case poet = matthew arnold.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.