noun, plural zoos.

Also called zoological garden. a parklike area in which live animals are kept in cages or large enclosures for public exhibition.
Informal. a place, activity, or group marked by chaos or unrestrained behavior.

Origin of zoo

First recorded in 1840–50; first two syllables of zoological garden taken as one syllable


a combining form meaning “living being,” “animal,” used in the formation of compound words: zoometry; zooplankton.
Also especially before a vowel, zo-.

Origin of zoo-

combining form representing Greek zôion animal
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for zoo

circus, menagerie, asylum, shambles, madhouse

Examples from the Web for zoo

Contemporary Examples of zoo

Historical Examples of zoo

  • I knew there was a big menagerie there, Cross's Zoo, and that I should find some lions for sale.

    My Double Life

    Sarah Bernhardt

  • The zoo attendants might talk and entirely spoil their scheme.

    The Mind Master

    Arthur J. Burks

  • "I've been to the zoo lots of times," she said to the girl next to her.

    The Hunters

    William Morrison

  • They say there is a country where the elephants are wild,And never even heard of our Zoo.

  • Has the reader ever visited that famous resort of youth, the Zoo?

    Follow My leader

    Talbot Baines Reed

British Dictionary definitions for zoo


noun plural zoos

a place where live animals are kept, studied, bred, and exhibited to the publicFormal term: zoological garden

Word Origin for zoo

C19: shortened from zoological gardens (originally applied to those in London)


before a vowel zo-

combining form

indicating animalszooplankton

Word Origin for zoo-

from Greek zōion animal
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

Word Origin and History for zoo

c.1847, short for Zoological Gardens of the London Zoological Society, established 1828 in Regent's Park to house the society's collection of wild animals. From comb. form of Greek zoion "an animal," literally "a living being," from PIE root *gwei- "to live, life" (cf. Greek bios "life," Old English cwicu "living;" see bio-). Slang meaning "crowded and chaotic place" first recorded 1935.

Online Etymology Dictionary, © 2010 Douglas Harper

zoo in Medicine



Animal; animal kingdom:zoonosis.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Idioms and Phrases with zoo


see it's a zoo.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.