1. Of the black colour of soot
   - soot-black

See also: achromatic, neutral

• observation post
• observation station
• observation tower
• observational
• observator
• observatory
• observe
• observed
• observed fire
• observer
• observer's meridian
• observing
• observingly
• obsess
• obsessed
• obsession
• obsessional
• obsessionally
• obsessive
• obsessive-compulsive
• obsessive-compulsive disorder
• obsessive-compulsive personality
• obsessively
• obsessiveness
• obsessivity