HIGHNESS, n. hi'ness. Elevation above the surface; loftiness; altitude; highth.1. Dignity; elevation in rank, character or power.2. Excellence; value.3. Violence; as the highness of wind.4. Great amount; as the highness of price.5. Acuteness; as the highness of a note or voice.6. Intenseness, as of heat.7. A title of honor given to princes or other men of rank.