Save This Word!

a combining form meaning “likeness,” used especially in the names of living organisms and organic structures that resemble the thing named by the initial element: coreopsis.
Test how much you really know about regular and irregular plural nouns with this quiz.
Question 1 of 9
Which of the following nouns has an irregular plural form?

Origin of -opsis

From the Greek word ópsis appearance, sight
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022


What does -opsis mean?

The combining form -opsis is used like a suffix meaning “likeness” or “resemblance.” It is rarely used in scientific terms, especially in medicine.

The form -opsis comes from Greek ópsis, meaning “appearance” and “sight.” Related to ópsis are ophthalmós, “eye,” which gives us the combining form ophthalmo-, as well as ṓps, “eye” or “face,” which is the root of combining forms such as opto-, -opia, and -opsia. The Latin cognate of ópsis, ophthalmo-, and ṓps is oculus, “eye,” the source of the combining form oculo- and the noun monocle. Learn more at our entries for each word.

What are variants of -opsis?

While -opsy is not a variant of -opsis, the two combining forms have a common origin. Want to know more? Read our Words That Use article for -opsy.

Examples of -opsis

One example of a scientific term that features the form -opsis is stereopsis, meaning “stereoscopic vision; the ability to perceive depth.”

The stere- part of the word means “solid,” particularly in reference to three-dimensionality, from Greek stereós. The form -opsis means “likeness.” Stereopsis roughly translates to “solid likeness.”

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

Not every word that ends with the exact letters -opsis, such as synopsis, is necessarily using the combining form -opsis to denote “likeness.” Learn why synopsis means “summary” at our entry for the word.

Break it down!

The combining form kore- comes from Greek kóris, meaning “bedbug.” With this in mind, what does the seed of a plant of the genus Coreopsis look like?

How to use -opsis in a sentence

British Dictionary definitions for -opsis


n combining form
indicating a specified appearance or resemblancemeconopsis

Word Origin for -opsis

from Greek opsis sight
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