An overpulse is a brief spike in voltage or current that shoots past the steady-state operating limits of a circuit. These transients can be generated by switching inductive loads, lightning strikes, or rapid load changes. If not clamped by protective devices, they can degrade semiconductor junctions or trigger false logic states.
Heard on the job
Check the scope trace on the relay coil; we're getting a massive overpulse when it de-energizes.