Stiffness
Stiffening, Rigidity
noun, verbal noun
こうちょく
硬い （かたい） Stiff, Hard, Firm
硬直 （こうちょく） Stiffness, Stiffening, Rigidity
Something with Rigidity 硬直 is stiff 硬 and fixed 直 in place.
Koichi こう almost chocked ちょく on his own Rigidity.