to death, fatally, mortally
to death, terribly, utterly
ruinously, perniciously, disastrously, fatally
harmfully, injuriously
Том был смертельно ра́нен в бо́ю.
Tom was fatally wounded in the battle.
Беовульф был смертельно ра́нен в бо́ю.
Beowulf was fatally wounded in the battle.