Definition of "declivity" in English

noun

1. (geomorphology) The downward slope of a curve.

   • 1780, Theodore Augustine Mann, A Treatise on Rivers and Canals, Philosophical Transactions of the Royal Society of London, Volume 69: For the Year 1779, Part II, 582, The velocity of flowing waters is very far from being in proportion to the quantity of declivity in their bed: […] .
   • 1908 [Charles Griffin & Company], John Harvard Biles, The Design and Construction of Ships, Volume I: Calculations and Strength, 2009, Europāischer Hochschulverlag (Salzwasser-Verlag), page 216, The declivity of the keel blocks varies slightly with the size of the vessel. The larger the vessel, the less the declivity.

2. A downward bend in a path.

3. (entomology) An inward curve of the exoskeleton of an insect, such as between body segments; a segment of an insect's body where the exoskeleton curves inward.

   • 1979, Entomology Circular, Issue 200, Part 366, Division of Plant Industry, page number not shown, Males of all species have more developed armature of the elytral declivity than females (Figs. S, 6, 8, 9, 11-14).