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pi·o·neer (pīə-nîr)
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n.
1. One who ventures into unknown or unclaimed territory to settle.
2. One who opens up new areas of thought, research, or development: a pioneer in aviation.
3. A soldier who performs construction and demolition work in the field to facilitate troop movements.
4. A species that is typically among the first to become established in a bare, open, or disturbed area.
adj.
1. Of, relating to, or characteristic of early settlers: the pioneer spirit.
2. Leading the way; trailblazing: a pioneer treatment for cancer.
v. pi·o·neered, pi·o·neer·ing, pi·o·neers
v.tr.
1.
a. To venture into (an area) or prepare (a way): rockets that pioneered outer space.
b. To settle (a region).
2. To initiate or participate in the development of: surgeons who pioneered organ transplants.
v.intr.
To act as a pioneer: pioneered in development of the laser.

[French pionnier, from Old French peonier, foot soldier, from peon, from Medieval Latin pedō, pedōn-, from Late Latin, one who has broad feet, from Latin pēs, ped-, foot; see ped- in the Appendix of Indo-European roots.]

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:

    Indo-European Roots

    Semitic Roots

    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.