One who convokes or calls together; a person who summons or convenes an assembly.
From Latin convocans (present participle of convocare, 'to call together'), from com- (with) and vocare (to call). The -ant suffix marks someone who performs an action.
Convocant is extremely rare in modern English, but it perfectly describes a role that's still crucial—the person who initiates gathering and calls people together. Medieval bishops, for example, were convocants when they summoned assemblies.
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