1. The act of inclining or the state of being inclined; a bend or tilt: The inclination of the child's head suggested sleep.
a. A deviation or the degree of deviation from the horizontal or vertical; a slant: the steep inclination of a roof.
b. The angle between two lines or planes: the inclination of the comet's orbit with respect to that of Earth.
c. An inclined surface; a slope.
a. A characteristic disposition or tendency to act in a certain way; a propensity: "I shall indulge the inclination so natural in old men, to be talking of themselves" (Benjamin Franklin).
b. A preference or liking: his musical inclinations.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.