The story
- Latin · derived from-itās“-ity”
- Late Latin · derived fromsēriōsus“serious”
- Medieval Latin · borrowed fromsēriōsitās
- English todayseriosity
From Medieval Latin sēriōsitās, from Late Latin sēriōsus (“serious”) + Latin -itās (“-ity”).
Etymology from Wiktionary, CC BY-SA 4.0.