Murder
Murderer
noun
When you kill a person that's murder.
The readings are the kun'yomi vocab readings. So, if you know 人's reading as a vocab word and 殺す's reading, you should be able to read this word. Just note that ころし goes to ごろし due to rendaku.
その男は人殺しです。
That man is a murderer.
自分の子を戦場に送り出して、人殺しをさせたい人なんていませんよ。
No one wants to send their own child to the battlefield to become a killer.
SNSで悪口を言ってる人は全員、自分が人殺しをしているかもしれないってことを考えた方がいいよ。
People who speak ill of others on social media should consider that they might be committing murder in a sense.