Poet and blundering scribbler (7)
I believe the answer is:
notepad
'scribbler' is the definition.
(I've seen this before)
'poet and blundering' is the wordplay.
'blundering' indicates anagramming the letters (I've seen 'blunder' mean this).
'poet'+'and'='poetand'
'poetand' is an anagram of 'NOTEPAD'.
(Other definitions for notepad that I've seen before include "On which one writes" , "Memo-block" , "Block writer might have" , "writer's block" , "scribbler" .)