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