distress signal

This term is used in high-stakes emergency contexts, primarily within maritime, aviation, and wilderness survival scenarios. It carries an urgent, life-or-death connotation, signaling a state of absolute necessity where the sender can no longer manage the crisis independently.

While "signal" can be a general term for any communication, adding "distress" narrows the scope to a formal request for rescue. In professional contexts, this refers to specific standardized codes, such as the "Mayday" radio call or the firing of a red flare, rather than a casual plea for help.