Wiktionary
n. A message left by someone who later attempts or commits suicide, usually explaining the reason for the attempt.
Wikipedia
A suicide note or death note is a message left behind before a person has committed suicide, or who intends to commit suicide.
It is estimated that 25–30% of suicides are accompanied by a note. According to Gelder, Mayou and Geddes (2005) one in six leaves a suicide note. The content can be a plea for absolution or blaming family and friends for life's failings. However, incidence rates may depend on ethnicity, method of suicide, and cultural differences, and may reach rates as high as 50% in certain demographics. A suicide message can be a written note, an audio message, or a video.
"Suicide Note" is a two-part song by the American heavy metal band Pantera from their eighth studio album, The Great Southern Trendkill. The first half of the song was released as the album's second single in 1996. It is Pantera's highest charting song on the Billboard Album Rock Tracks chart (now known as the Hot Mainstream Rock Tracks), peaking at #10. The combination total time is 9 minutes 3 seconds.