ngo bo

Another base word with many variations -- good to learn -- is ngo bo. It's translated as essence, the very thing, and so on. It is used to pinpoint a specific feature, essence, main trait, nature identity, for various terms and constructs.

In Sanskrit this is svabhava.

Variations of this is ngo bo nyid, the very essence, self-nature, fundamental mode.

ngo bo nyid sku, is the essence body of a buddha, svabhavikakaya. Depending on the presentation, in various schools, it has a somewhat different meaning. In the Gelug tradition this body is sometimes presented as the emptiness of the other bodies of the Buddha (mind, enjoyment, emanation).

Even the word body is somewhat misleading, as a mind is not a body, it's rather the collection of specific parts of a Buddha. An enlightened being still has a body (emanation body), speech (enjoyment body) and mind (emptiness of a Buddha's mind that experiences everything at the same time). Any of these three parts has no self-existance, existing from its own side, and this is the essence body.