lightning mapper

Wiktionary

1. n. meteorology A system that displays a map of the position of recorded or real-time lightning discharges relative to the user or other objects.
2. n. instrumentation The component of such a system that gathers the required data, comprised of an interconnected network of electric field change sensors that measure the time of arrival of electric field pulses from the strokes in a lightning flash. 2D maps require 3 such sensors, 3D maps require 4.