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um·pire (ŭmpīr)
1. Sports A person appointed to rule on plays, especially in baseball.
2. A person appointed to settle a dispute that mediators have been unable to resolve; an arbitrator.
v. um·pired, um·pir·ing, um·pires
To act as referee for; rule or judge.
To be or act as a referee or an arbitrator.

[Middle English (an) oumpere, (an) umpire, alteration of (a) noumpere, a mediator, from Old French nonper : non-, non- + per, equal, even, paired (from Latin pār; see PAIR).]

Word History: Had it not been for the linguistic process known as false splitting or juncture loss, the angry, anguished cry heard at sports events, "Kill the ump," could have been "Kill the nump." In the case of umpire we can almost see false splitting in action by studying the Middle English Dictionary entry for noumpere, the Middle English ancestor of our word. Noumpere comes from Old French nonper, made up of non, "not," and per, "equal." As an impartial arbiter of a dispute between two people, the umpire is not equivalent to or a partisan of either of them. In Middle English the earliest recorded form is noumper (about 1350); the earliest form without an n is owmpere, recorded in a document dated 1440. How the n was lost can be seen if we compare the sequence a noounpier in a text written in 1426-1427 with the sequence an Oumper from a text written probably around 1475. In an Oumper, the n has become attached to the indefinite article, giving us an instead of a and, eventually, umpire instead of numpire. The same sort of false splitting has altered the forms of other words as well. Apron, for example, used to be napron, and adder used to be nadder. The reverse process has also occurred in the history of English: words that originally began with vowels acquired an n from a preceding indefinite article. Nickname comes from an obsolete phrase an eke name, "an additional name." Newt comes from an eute. A variant of the Middle English word eute still survives as eft, "a newt."

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.