Gravy is a sauce

Sauce

In cooking, a sauce is liquid, creaming or semi-solid food served on or used in preparing other foods. Sauces are not normally consumed by themselves; they add flavor, moisture, and visual appeal to another dish. Sauce is a French word taken from the Latin salsus, meaning salted...

 made often from the juices that run naturally from meat or vegetables during cooking. In North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 the term can refer to a wider variety of sauces and gravy is often thicker than in Britain

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

. The gravy may be further coloured and flavoured with gravy salt (a simple mix of salt and caramel food colouring) or gravy browning (gravy salt dissolved in water) or ready-made cubes

Bouillon cube

A bouillon cube [ˈbuːjɒn kjuːb] or stock cube is dehydrated bouillon or stock formed into a small cube about 15 mm wide. It is made by dehydrating vegetables, meat stock, a small portion of fat, salt and seasonings and shaping them into a small cube...

 and powders can be used as a substitute for natural meat or vegetable extracts.