1. A crust discharged from and covering a healing wound.
2. Scabies or mange in domestic animals or livestock, especially sheep.
a. Any of various plant diseases caused by fungi or bacteria and resulting in crustlike spots on fruit, leaves, or roots.
b. The spots caused by such a disease.
4. Slang A person regarded as contemptible.
a. A worker who refuses membership in a labor union.
b. An employee who works while others are on strike; a strikebreaker.
c. A person hired to replace a striking worker.
intr.v. scabbed, scab·bing, scabs
1. To become covered with scabs or a scab.
2. To work or take a job as a scab.
[Middle English, from Old Norse skabb.]
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.