expression, suru verb (irregular)
to die; to pass away; to depart this world
A formal, literary euphemism for death, often used in obituaries, condolences, or solemn contexts. The phrase literally means 'to be separated by the boundary between the world of the living and the world of the dead.'
See also: 幽冥 (ゆうめい)
祖父は昨晩、幽明境を異にしました。
My grandfather passed away last night.
He died at a young age.