What is the meaning of Downgrade?

A reduction of a rating, as a financial or credit rating.

A downhill gradient on a road or railway.

A reduction in quality; a descent towards an inferior state.

To place lower in position.

To reduce in complexity, or remove unnecessary parts; to dumb down.

To disparage.

to reduce the official estimate of a storm's intensity.

To revert software back to an older version.

Source: wiktionary.org