1 definition by SunnyDaylily

A phrase posted at the beginning of various posts, articles, or blogs. Its purpose is to warn people with issues such as PTSD, Depression, Suicidal thoughts/behaviors, past drug/alcohol addictions or victims of things like Rape and Abuse that there is content ahead that may trigger a traumatic flashback or could possibly even make them want to harm themselves ahead. Sometimes, for people who have harmed themselves in the past, just one picture or post about self-harm can make them want to harm themselves again.

Trigger warning are necessary before posts that have to do with traumatic events, such as rape, cutting, suicide, drug use, and other PTSD influencing subject matter. They should never be used as a joke or joked about (unless you are around people you know will not be triggered by it).
Before posting a picture of someone cutting themselves, one might include the phrase "Trigger Warning" before the post.
by SunnyDaylily November 29, 2015