1. Appropriateness of behavior or conduct; propriety: "In the Ireland of the 1940's ... the stolidity of a long, empty, grave face was thought to be the height of decorum and profundity" (John McGahern).
2. decorums The conventions or requirements of polite behavior: the formalities and decorums of a military funeral.
3. The appropriateness of an element of an artistic or literary work, such as style or tone, to its particular circumstance or to the composition as a whole.
[Latin decōrum, from decōrus, becoming, handsome; see DECOROUS.]
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.