Severity is how serious or how harsh something is. The severity of the illness, severity of the sentence, judged by severity.
In medicine it is measured on defined scales — mild, moderate, severe — and treatment often follows the grade rather than the diagnosis. In sentencing it means harshness. In weather warnings it decides the colour. Note severe; and that the Latin behind it is about strictness, which is why severity of manner and severity of illness are the same word.
1nounseverityHow serious or how harsh something is.
“Doctors were shocked by the severity of his injuries.”
severity is a degree of seriousness.
Latin severitas comes from severus, strict or serious. Persevere and asseverate come from the same strictness.
Latin
sevēritās
Middle French
severite
Middle English
severity
English, today
severity
From Middle English severity, from Middle French severite (modern French sévérité), from Latin sevēritās. by surface analysis, severe + -ity.
Etymology from Wiktionary, CC BY-SA