Unnatural Death, Accidental Death
noun, verbal noun
A strange death is one that doesn't seem right. It's an unnatural death, and probably an accidental death (ie wasn't caused by natural causes).
へんし
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.
やば！「返信ください」がタイプミスでオートコレクトされて「変死してください」になってた。
Yikes! "Please reply" was mistyped and autocorrected to "Please die unnaturally."
今朝、社長が車で変死しているのが見つかったんだって！
This morning, they found the president dead in his car under unnatural circumstances!
あそこの山でエイリアンの変死体が発見されたというウワサがあります。
There's a rumor that an alien corpse was found in the mountains over there.