Poe, limit, terribly rude (8)
I believe the answer is:
impolite
'rude' is the definition.
(similar in meaning)
'poe limit terribly' is the wordplay.
'terribly' is an anagram indicator.
'poe'+'limit'='poelimit'
'poelimit' with letters rearranged gives 'IMPOLITE'.
(Other definitions for impolite that I've seen before include "Bad mannered" , "Rude and uncivil" , "Having bad manners" , "Lacking good manners" , "Discourteous" .)