Suicide
noun, verbal noun
A self kill is when you kill yourself. That's suicide.
じさつ
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
自殺をしてはいけません。
You must not commit suicide.
自殺が頭によぎったら、すぐヘルプラインに電話してください。
When thoughts of suicide arise, please call a helpline for help.
フォーラムで色々な人とやりとりをするうちに、自然と自殺を思いとどまることができたという人もいました。
There are people who, through interacting with various individuals on forums, naturally refrained from suicidal thoughts.