expeditionary

American  

[ek-spi-dish-uh-ner-ee] / ˌɛk spɪˈdɪʃ əˌnɛr i /

adjective

1. pertaining to or composing an expedition.

   an expeditionary force.

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expeditionary British  

/ ˌɛkspɪˈdɪʃənərɪ /

adjective

1. relating to or constituting an expedition, esp a military one

   an expeditionary force

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Other Word Forms

• preexpeditionary adjective

Etymology

Origin of expeditionary

First recorded in 1700–10; expedition + -ary

Example Sentences

On Friday, the Pentagon announced that an additional expeditionary unit of 2,500 Marines was being deployed to the region to support the effort.

From Los Angeles Times • Mar. 15, 2026

Mr. Hertling would return to the Middle East repeatedly over the course of the terror wars, living firsthand the “pendulum swing between expeditionary and enduring” that would dog the U.S. armed forces across two decades.

From The Wall Street Journal • Mar. 9, 2026

The United States Marines are the country’s elite shock troops and an expeditionary force that specializes in amphibious assaults.

From Salon • Jun. 12, 2025

Chinese records appear to first mention the island in AD239, when an emperor dispatched an expeditionary force to it - a fact Beijing uses to back its territorial claim.

From BBC • Oct. 14, 2024

A British expeditionary force was about to sail across the English Channel and link up with French forces fighting in Belgium.

From "The War to End All Wars: World War I" by Russell Freedman