From The Collaborative International Dictionary of English v.0.48:
Rigidity \Ri*gid"i*ty\, n. [L. rigiditas: cf. F. rigidit['e].
See Rigid.]
1. The quality or state of being rigid; want of pliability;
the quality of resisting change of form; the amount of
resistance with which a body opposes change of form; --
opposed to flexibility, ductility, malleability, and
softness.
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2. Stiffness of appearance or manner; want of ease or
elegance. --Sir H. Wotton.
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3. Severity; rigor. [Obs. orR.] --Bp. Burnet.
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Syn: Stiffness; rigidness; inflexibility.
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