"Arm-turning pin" or "second form".
Nikyo builds on Ikkyo (first Osae-Waza form) but differs significantly in the build-up: The principle of Nikyo is based on a rather horizontal circular movement with which uke is "sucked in" before being guided to the ground via the wrist lock.
Essential features are the twisting and locking of the wrist via pressure on the base of the thumb and the positioning of uke's hand on the collarbone.
The Nikyo immobilisation pin ("double-teacup" pin) is clearly different from the Ikkyo pin.
Nikyo can be understood as a continuation technique applied when Ikkyo does not work.
