Synonyms for Stiffness (same or very similar meaning)
WordNet sense 1 (the inelegance of someone stiff and unrelaxed (as by embarrassment)):
awkwardness, clumsiness, gracelessness
WordNet sense 2 (excessive sternness):
hardness, harshness, inclemency, rigor, rigorousness, severeness, severity, rigour, rigourousness
From the ODE community, based on WordNet
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