- the quality of having a level surface without raised areas or indentations；lack of hills in a landscape
- 1. the quality of having a level surface without raised areas or indentations the flatness of the external surface make sure that the paper is of uniform flatness
- ▪ lack of hills in a landscape the flatness of the desert stretched out uninterrupted for miles extensive areas of relative flatness
- 2. lack of emotion or enthusiasm; dullness neither the editing nor the score do much to help the film's emotional flatness there's no escaping the flatness of the characters
- ▪ lack of activity of trade, prices, etc.; sluggishness investors seem content with progress, despite the flatness of revenue and profits
- 3. loss of effervescence in a sparkling drink.
- ▪ loss of air in something inflated, such as a tire.
- ▪ British the condition of a battery having exhausted its charge.
- 4. the quality of a musical sound being below normal pitch the flatness of the vocals