zoo

The combining form zoo– is used like a prefix meaning “living being” or “animal.” It is often used in scientific terms, especially in biology.

The form zoo– comes from Greek zôion, meaning “animal.”

What are variants of zoo-?

When combined with words or word elements that begin with a vowel, zoo– becomes zo–, as in zooid.

When combined as a suffix, zoo– becomes –zoa or –zoon, as in protozoa or ectozoon. Want to know more? Read our Words That Use articles for zo-, -zoa, and -zoon.

An example of a word you may have encountered that features zoo– is zoology, “the science or branch of biology dealing with animals.”

We know zoo– means “animal,” and the –logy portion of the word refers to “science,” from Greek logía. Zoology literally translates to “animal science.”

The word zoo is ultimately shortened from zoological garden; zoological is the adjective form of zoology.

What are some words that use the combining form zoo-?

• zoobiotic
• zoochlorella
• zoometry
• zoonosis
• zoophagous
• zoophile
• zoospore

What are some other forms that zoo– may be commonly confused with?

• oo-
• zygo-

Not every word that begins with the exact letters zoo– or zo-, such as zoom or zooty, is necessarily using either combining form to denote “animal.” Learn why zooty means “flamboyant” at our entry for the word.

The combining form –metry means “the process of measuring.” With this in mind, what is zoometry?