army ant

American

noun

any of the chiefly tropical ants of the suborder Dorylinae that travel in vast swarms, preying mainly on other insects.

army ant British

noun

Also called: legionary ant. any of various mainly tropical American predatory ants of the subfamily Dorylinae, which live in temporary nests and travel in vast hordes preying on other animals See also driver ant

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of army ant

First recorded in 1870–75

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In Costa Rica, a rufous-vented ground cuckoo snatches a cicada fleeing an army ant swarm.

From BBC • Mar. 25, 2026

An individual army ant is practically blind and has a minuscule brain that couldn’t begin to fathom their elaborate collective movement.

From Washington Post • Apr. 6, 2018

A second is that it’s very possible there’s more governing army ant behavior than two simple rules.

From Washington Post • Apr. 6, 2018

Top: Ecitophya bicolor with an Eciton burchelli army ant.

From Scientific American • Dec. 10, 2012

At last, above the crest of the last hillock he had surmounted, two tiny antennae appeared, then the black glistening head of an army ant, the forerunner of its horde.

From The Mad Planet by Leinster, Murray

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023