unable to bend or be forced out of shape; not flexible
(of a person or part of their body) stiff and unmoving, especially as a result of shock or fear
not able to be changed or adapted
not adaptable in outlook, belief, or response
a lorry which is not articulated.
capable of bending easily without breaking
able to be easily modified to respond to altered circumstances
(of a person) ready and able to change so as to adapt to different circumstances