1. One that interferes with the affairs of others, often for selfish reasons; a meddler.
2. One that intrudes in a place, situation, or activity: "When these interlopers choke out native species, ecologists see a danger signal" (William K. Stevens).
a. One that trespasses on a trade monopoly, as by conducting unauthorized trade in an area designated to a chartered company.
b. A ship or other vessel used in such trade.
[INTER- + probably Middle Dutch lōper, runner (from lōpen, to run).]
Word History: The word interloper has its origin in the time when England was embarking on the course that would lead to the British Empire. Interloper is first recorded in the late 1500s in connection with the Muscovy Company, the earliest major English trading company (chartered in 1555). The word was soon being used in connection with independent traders competing with the East India Company (chartered in 1600). These companies were established as monopolies, and independent traders, called interlopers, were not welcome. The term is probably partly derived from Dutch, the language of one of the great trade rivals of the English at that time. The inter- is simply the prefix inter-, which English has borrowed from Latin, meaning "between, among." The element -loper is probably related to the same element in landloper, "vagabond," a word adopted from Dutch landloper, with the same sense and composed of land, "land," and loper, from lopen, "to run, leap." The word interloper soon came to be used in the extended sense "meddler, person who intrudes in others' affairs" by the 1630s.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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.