From The Collaborative International Dictionary of English v.0.48:
Serenity \Se*ren"i*ty\, n. [L. serenuas: cf. F.
s['e]r['e]nit['e].]
1. The quality or state of being serene; clearness and
calmness; quietness; stillness; peace.
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A general peace and serenity newly succeeded a
general trouble. --Sir W.
Temple.
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2. Calmness of mind; eveness of temper; undisturbed state;
coolness; composure.
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I can not see how any men should ever transgress
those moral rules with confidence and serenity.
--Locke.
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Note: Serenity is given as a title to the members of certain
princely families in Europe; as, Your Serenity.
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