How to document a dictionary in JSDoc?

According to the JSDoc 3 docs:

Arrays and objects (type applications and record types)

An object with string keys and number values:

{Object.<string, number>}

So it would be:

/** @type {{locales: Object.<string, {name: string, lang: string}>}} */
var CONF = {
    locales: {
        en: {
            name: "English",
            lang: "en-US"
        },
        es: {
            name: "Spanish",
            lang: "es-ES"
        }
    }
};

Cleaner, using @typedef

/**
 * @typedef {{name: string, lang: string}} locale
 */
/**
 * @type {{locales: Object.<string, locale>}}
 */
var CONF = {
    locales: {
        en: {
            name: "English",
            lang: "en-US"
        },
        es: {
            name: "Spanish",
            lang: "es-ES"
        }
    }
};