Victim
noun
You already learned that 犠牲 means "victim," so when you add someone to that, it still means victim.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
その飛行機事故では、事故で多くの犠牲者がでました。
Many victims appeared from the airplane accident.