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

acclivity \accliv"ity\, n.; pl. acclivities. l. acclivitas,
   fr. acclivis, acclivus, ascending; ad + clivus a hill, slope,
   fr. root kli to lean. see lean.
   a slope or inclination of the earth, as the side of a hill,
   considered as ascending, in opposition to declivity, or
   descending; an upward slope; ascent.
   1913 webster
see also:
acclivities lean 

[2] : WordNet (r) 2.0

acclivity
     n : an upward slope or grade as in a road; "the car couldn't
         make it up the rise" syn: ascent, rise, raise, climb,
          upgrade ant: descent
see also:
ascent rise raise climb upgrade descent 

Acclivity >> A Words
Acclivity, definition of term: Acclivity
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