A class action lawsuit is a lawsuit in which a group of people with the same or similar injuries caused by the same product or action file suit against the defendant as a group. Other names for class action lawsuits include “mass tort litigation” or “multi-district litigation” (MDL).
A "class action" lawsuit is one in which a group of people with the same or similar injuries caused by the same product or action sue the defendant as a group. Other names for lawsuits brought by a number of people who suffered similar harm or losses are "mass tort litigation" and "multi-district litigation.