The followings terms are used in SCR specifications:
Latching current : The latching current is the value of on stat e current required to maintain conduction at the instant when the gate current is removed. To trigger a thyristor a gate current greater than the maximum device gate trigger current IGT must be applied until the on state current IT rises above the maximum latching current IL. This condition must be met at the lowest junctions temperature. Therefore it is the minimum value of anode current which it most attain during turn on process to maintain conduction when gate signal is removed. It may also define as the minimum current that must be applied through the cathode and anode of an SCR in order in order to turn from the off state to the on state while its gate trigger current is beings correctly applied.