GeometryJsonType:
    | "esriGeometryPoint"
    | "esriGeometryMultipoint"
    | "esriGeometryPolyline"
    | "esriGeometryPolygon"
    | "esriGeometryEnvelope"

Types of geometry. Geometry JSON objects don't reference these types, but they appear within services to describe the type of geometries in layers.