Blast you, endless moaners! I get the message! (3,2,4)
I believe the answer is:
say no more
'i get the message' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.
'blast you endless moaners' is the wordplay.
'blast' indicates an anagram (I've seen 'blasted' mean this).
'endless' means to remove the last letter.
'you' with its last letter taken away is 'yo'.
'yo'+'moaners'='yomoaners'
'yomoaners' anagrammed gives 'SAY NO MORE'.
Can you help me to learn more?
(Other definitions for say no more that I've seen before include "I understand the implication!" , "Further words are unnecessary" , "It speaks for itself" , "Not another word!" .)