The phrase "major trigger" means something that causes a strong emotional or physical reaction in a person. It can be an event or situation that brings about intense feelings, often negative or distressing. Full definition
They can also be helpful for dealing with trauma and overwhelming emotions, major triggers for behavioral problems in teens. (sundancecanyonacademy.com)
This is with a view to establishing guidelines for reporting elections to maximize the contributions of the media to democracy; eliminating hate speech and violence - inciting reporting, which are major triggers of conflict in the region. (inecnews.com)
Major triggers include a poor diet, food allergies and sensitivities, toxins, antibiotics, synthetic drugs, and stress. (mindbodygreen.com)