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Webster 1913 Edition
Sereneness
Se-rene′ness
,Noun.
 Serenity. 
Feltham.
 Webster 1828 Edition
Sereneness
SERE'NENESS
,Noun.
  Definition 2025
sereneness
sereneness
English
Noun
sereneness (usually uncountable, plural serenenesses)
- The property of being serene.
 
Usage notes
- Plural very rare; "serenities" much more common.