in·cu·bus (ĭnkyə-bəs, ĭng-)
n. pl. in·cu·bus·es or in·cu·bi (-bī′)
1. An evil spirit supposed to descend upon and have sexual intercourse with women as they sleep.
2. A nightmare.
3. An oppressive or nightmarish burden.
[Middle English, from Late Latin, alteration of Latin incubō, from incubāre, to lie down on; see INCUBATE.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 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:
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