1. Given to or characterized by unwholesome thoughts or feelings, especially of death or disease: read the account of the murder with a morbid interest.
a. Of, relating to, or caused by disease; pathological or diseased: morbid changes in tissues.
b. Psychologically unhealthy or unwholesome: a morbid fear of heights.
[Latin morbidus, diseased, from morbus, disease; see mer- in the Appendix of Indo-European roots.]
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.