The word(s) "slain" appears 15 time(s) in 14 verse(s) in Quran in Muhammad Habib Shakir translation.

(11) And do not kill any one whom Allah has forbidden, except for a just cause, and whoever is slain unjustly, We have indeed given to his heir authority, so let him not exceed the just limits in slaying; surely he is aided.

(12) So they went on until, when they met a boy, he slew him. (Musa) said: Have you slain an innocent person otherwise than for manslaughter? Certainly you have done an evil thing.

(13) And (as for) those who fly in Allah's way and are then slain or die, Allah will most certainly grant them a goodly sustenance, and most surely Allah is the best Giver of sustenance.

(14) So when you meet in battle those who disbelieve, then smite the necks until when you have overcome them, then make (them) prisoners, and afterwards either set them free as a favor or let them ransom (themselves) until the war terminates. That (shall be so); and if Allah had pleased He would certainly have exacted what is due from them, but that He may try some of you by means of others; and (as for) those who are slain in the way of Allah, He will by no means allow their deeds to perish.