Synonyms for Severeness (same or very similar meaning)
WordNet sense 1 (used of the degree of something undesirable e.g. pain or weather):
badness, severity
WordNet sense 2 (something hard to endure):
asperity, grimness, hardship, rigor, rigorousness, rigour, rigourousness
WordNet sense 3 (extreme plainness):
austereness
WordNet sense 4 (excessive sternness):
hardness, harshness, inclemency, stiffness
From the ODE community, based on WordNet
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