Suffocation
Choking
noun, する verb, の adjective
Suffocate to the point that you have no breath left and you'll die of suffocation. Chew your food and this shouldn't happen!
ちっそく
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
死因は首を絞められたことによる窒息です。
The cause of death was suffocation due to strangulation of the neck.