amphibious

American  

[am-fib-ee-uhs] / æmˈfɪb i əs /

adjective

1. living or able to live both on land and in water; belonging to both land and water.

2. Also capable of operating on both land and water.

   amphibious vehicles.

3. of or relating to military operations by both land and naval forces against the same object, especially to a military attack by troops landed by naval ships.

4. trained or organized to fight, or fighting, on both land and sea.

   amphibious troops.

5. combining two qualities, kinds, traits, etc.; of or having a mixed or twofold nature.

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amphibious British  

/ æmˈfɪbɪəs /

adjective

1. able to live both on land and in the water, as frogs, toads, etc

2. designed for operation on or from both water and land

3. relating to military forces and equipment organized for operations launched from the sea against an enemy shore

4. having a dual or mixed nature

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Other Word Forms

• amphibiously
  adverb
• amphibiousness
  noun
• nonamphibious
  adjective
• nonamphibiously
  adverb
• nonamphibiousness
  noun

Etymology

Origin of amphibious

First recorded in 1635–45; from Latin amphibius, from Greek amphíbios “living a double life”; see amphi-, bio-, -ous

Explanation

If you can drive your car down the highway and then go off road and ford a few rivers, too, you've got an amphibious vehicle — something that works on land and in the water, too. Amphibious also describes animals that can live on land or in the water — like frogs and toads — and comes from the Greek roots amphi "both" and bios "life." Military operations where both your army and your navy are involved — one attacking by land and the other by sea — are called amphibious assaults or amphibious operations.

Example Sentences

In addition to South Korea’s Thaad assets, two ships from the Japan-based USS Tripoli Amphibious Ready Group and the 31st Marine Expeditionary Unit are being sent to the Middle East.

From The Wall Street Journal • Mar. 20, 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 event is titled “Sea to Shore — A Review of Amphibious Strength” and will feature Vice President JD Vance.

From Los Angeles Times • Oct. 15, 2025

Amphibious ships are used to move assault troops to land quickly, especially in enemy territory.

From BBC • Feb. 14, 2024

The Fifth Marine Amphibious Corps was also the largest landing force in the history of the Marines.

From "Code Talker: A Novel About the Navajo Marines of World War Two" by Joseph Bruchac

Related Words

• floating
• marine
• maritime