The Collaborative International Dictionary of English v.0.48:

Austerity \Aus*ter"i*ty\, n.; pl. Austerities. [F.
   aust['e]rit['e], L. austerias, fr. austerus. See Austere.]
   1. Sourness and harshness to the taste. [Obs.] --Horsley.
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   2. Severity of manners or life; extreme rigor or strictness;
      harsh discipline.
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            The austerity of John the Baptist.    --Milton.
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   3. Plainness; freedom from adornment; severe simplicity.
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            Partly owing to the studied austerity of her dress,
            and partly to the lack of demonstration in her
            manners.                              --Hawthorne.
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