sudden

Sudden is an adjective meaning happening or occurring quickly and without warning, rather than gradually. It describes events, changes, or actions that are abrupt in time or appearance. The adverb form is suddenly, used to describe how something occurs.

Etymology: The word comes from Old French soudain, meaning “sudden,” ultimately from Latin subitus. The term entered English in the medieval period and has remained a common descriptor across domains.

Usage: Sudden often implies surprise or disruption. It can apply to physical phenomena (a sudden storm), health (a sudden onset of symptoms), or social or policy changes (a sudden shift in policy). In medical contexts, “sudden” is used with “onset” to indicate symptoms that appear abruptly, as in sudden onset chest pain. The word contrasts with gradual, incremental, or progressive.

Examples: Examples include “a sudden storm swept over the coast,” “the patient experienced a sudden onset of headaches,” “there was a sudden change in the corporation’s leadership,” and “she had a sudden realization.”

See also: suddenness, abrupt, instantaneous, unexpected, onset.