To Pass Away
To Become Deceased, To Die
intransitive verb, godan verb
なくなる
亡くなる （なくなる） To Pass Away, To Become Deceased, To Die
無くなる （なくなる） To Be Gone, To Run Out, To Be Lost, To Disappear
居なくなる （いなくなる、not on WK） To Disappear (Of People Or Animals), To Go (Away), To Leave, To No Longer Exist
死ぬ （しぬ） To Die
果てる （はてる） To End, To Die
亡くなる means To Die. 居なくなる means To Disappear (alive or dead).