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

This weekend, the USS Tripoli and the 31st Marine Expeditionary Unit entered the region.

From The Wall Street Journal • Mar. 31, 2026

Earlier this month, the San Diego-based USS Boxer and two warships from the 11th Marine Expeditionary Unit departed from Camp Pendleton to join the buildup of troops in the region.

From Los Angeles Times • Mar. 30, 2026

A statement came after Marines from the 31st Expeditionary Unit arrived in the Middle East on Saturday, the Journal reported.

From Barron's • Mar. 30, 2026

The Wall Street Journal is now reporting that Defense Secretary Pete Hegseth has authorized deploying elements of a Marine Amphibious Expeditionary Unit and an amphibious-ready group to the Middle East.

From Salon • Mar. 16, 2026

The government decided at the outset that the American Expeditionary Force would be made up mostly of draftees.

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