These characters had died by the end of the manga, anime or movie. Permanently.
Warning! Major spoilers abound from even looking at this list!
Death Notes: (pun intended)
Dragonball characters associated to this concept are generally villains, most heroic Dragonball characters are simply wished back to life after dieing, and thus are not on this list due to being brought back to life.
Voltron characters associated to this concept did not die in the American version, but in GoLion and Dairugger XV, with the single exception of Keyo who died in both countries versions of the series and Alfor who was always dead. A few others are debatable but only Keyo was officially killed in US continuity.
Transformers characters are also very sparsely featured on this concept page due to a variety of continuities repeatedly resurrecting deceased characters such as Optimus Prime, Megatron, and Starscream. Dinobot is one of the only characters of this franchise who has officially remained deceased.