Encouraged to be terribly rude with note (5)
I believe the answer is:
Here is my best explanation:
'encouraged' is the definition.
(I've seen this before)
'terribly rude with note' is the wordplay.
'terribly' indicates an anagram.
'with' indicates putting letters inside.
'note' becomes 'g' (musical note**).
'rude' anagrammed gives 'ured'.
'ured' going around 'g' is 'URGED'.
'to be' acts as a link.
(Other definitions for urged that I've seen before include "Strongly recommended", "Incited", "Beseeched", "Pressed", "Impelled - encouraged", "Exhorted or prodded", "Egged on", "Encouraged" and "Strongly advised".)