1. A self-propelled vehicle, usually electric, diesel, or steam-powered, for pulling or pushing freight or passenger cars on railroad tracks.
2. A driving or pulling force; an impetus: "The US could no longer serve as the locomotive for the world economy" (George Soros).
a. Of, relating to, or involved in locomotion.
b. Serving to put into motion or propel forward: "It may be that the founding fathers overestimated the locomotive force of the collective and mutual self-interest" (Ian Davidson).
2. Able to move independently from place to place.
3. Of or relating to a self-propelled locomotive.
4. Of or relating to travel.
[Latin locō, from a place, ablative of locus, place + Medieval Latin mōtīvus, causing motion; see MOTIVE.]
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.