Definition of flatness

• n. - The quality or state of being flat.
• n. - Eveness of surface; want of relief or prominence; the state of being plane or level.
• n. - Want of vivacity or spirit; prostration; dejection; depression.
• n. - Want of variety or flavor; dullness; insipidity.
• n. - Depression of tone; the state of being below the true pitch; -- opposed to sharpness or acuteness.