Type Alias RelativeTimeFormatPart

RelativeTimeFormatPart: {
    type: "literal";
    value: string;
} | {
    type: Exclude<NumberFormatPartTypes, "literal">;
    unit: RelativeTimeFormatUnitSingular;
    value: string;
}

An object representing the relative time format in parts that can be used for custom locale-aware formatting.

MDN.