whim (wĭm, hwĭm)
1. A sudden or capricious idea; a fancy: “More than five hundred of these men would never see another sunset, yet a holiday atmosphere prevailed; they joked with each other as they marched, dropping out again for blackberries when the whim struck them, despite stern new orders to the contrary” (William Marvel).
2. Arbitrary thought or impulse: “I dreamed of having the golden flesh, the huge muscles of half-naked gods and goddesses who did whatever they wanted to do, ruling the universe according to their whims” (John Edgar Wideman).
3. A vertical horse-powered drum used as a hoist in a mine.
on a whim
Done suddenly or impulsively: “I just took a trip. Lit off at night, drove six hundred miles to see an old friend, on a whim” (Marya Hornbacher).
[Short for whim-wham, fanciful object.]
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.