moo

American  

[moo] / mu /

verb (used without object)

mooed, mooing

1. to utter the characteristic deep sound of a cow; low.

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noun

plural

moos

1. a mooing sound.

moo British  

/ muː /

verb

1. (intr) (of a cow, bull, etc) to make a characteristic deep long sound; low

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interjection

1. an instance or imitation of this sound

Etymology

Origin of moo

First recorded in 1540–50; imitative

Example Sentences

Videos of the hippo went viral, memes were created, and visitor numbers at the zoo increased hugely as thousands flocked each weekend to catch a glimpse of Moo Deng.

From BBC • Apr. 8, 2026

Narongwit Chodchoy, who runs Khao Kheow Open Zoo, told AFP that the man, who entered Moo Deng's pen last month, had been found guilty by a local court.

From BBC • Apr. 8, 2026

“Tell everybody about the specialties,” the mayor said to Jessica and Marcos Moo, who smiled shyly as he started recording.

From The Wall Street Journal • Dec. 2, 2025

There’s nothing like your first time firing up “Mario Kart World” on a 4K TV and cruising through Moo Moo Meadows in a pack of two dozen goofy, hyperactive racers.

From The Wall Street Journal • Nov. 23, 2025

In other words, Moo of the lethal dose of each compound may be fatal when the two are combined.

From "Silent Spring" by Rachel Carson