IPA: /kənˈvʌlsɪvli/
KK: /kənˈvʌlsɪvli/
In a way that involves sudden, violent movements or spasms.
He shook convulsively after the shocking news.
Convulsively → It is formed from "con-" (meaning together) and "vulsus" (from "vulsa", meaning to pull or tear). The word describes an action that involves pulling or tearing together, often in a sudden or violent manner, which is characteristic of convulsions.
Think of 'pulling together' ('con-') in a sudden or violent way ('vulsus') — that's why convulsively refers to sudden, jerky movements.