[1] : The Collaborative International Dictionary of English v.0.48

steepness \steep"ness\, n.
   1. quality or state of being steep; precipitous declivity;
      as, the steepnessof a hill or a roof.
      1913 webster

   2. height; loftiness. obs. --chapman.
      1913 webster

[2] : WordNet (r) 2.0

steepness
     n : the property possessed by a slope that is very steep syn: abruptness,
          precipitousness ant: gradualness
see also:
abruptness precipitousness gradualness 

Steepness >> S Words
Steepness, definition of term: Steepness
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