suicidal

Short definition from Wiktionary

Adjective

1. 1
   Pertaining to suicide.
2. 2
   Likely to commit, or to attempt to commit, suicide.
3. 3
   Highly likely to certain to result in the deaths of the participants; dangerous or reckless to such a degree as to be tantamount to suicide for those taking part.
4. 4
   Extremely reckless.

Noun

1. 1
   Someone suicidal; someone likely to kill themselves.