mail bomb
noun[C]
ITukus(alsoemail bomb)anoccasionwhen manyemailmessagesaresentto asingleaddressat the sametime, forexampleas a way ofcomplainingorshowingangerabout something, or inordertoannoysomeone:
Mailbombschokedthemailserverand made itimpossiblefor us to getourrealmessages.
mail-bomb
verb[T]
Spammers mail-bombed thetradecommissionas a way toprotesttheinvestigation.