octopus
Americannoun
plural
octopuses, octopi-
any octopod of the genus Octopus, having a soft, oval body and eight sucker-bearing arms, living mostly at the bottom of the sea.
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something likened to an octopus, as an organization with many forms of far-reaching influence or control.
noun
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any cephalopod mollusc of the genera Octopus, Eledone, etc, having a soft oval body with eight long suckered tentacles and occurring at the sea bottom: order Octopoda (octopods)
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a powerful influential organization with far-reaching effects, esp harmful ones
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another name for spider
Etymology
Origin of octopus
1750–60; < New Latin < Greek oktṓpous (plural oktṓpodes ) eight-footed; see octo-, -pod
Explanation
An octopus is an eight-legged sea creature. Octopuses are intelligent animals, and have been shown to have great capacity for learning. (However, that doesn't stop people from grilling and eating them.) An octopus is a mollusk, which means it's a distant relation of slugs, snails, clams, and mussels. It's also a cephalopod, an animal with a large head and tentacles or arms. Of the other animals in these categories, octopuses are by far the smartest, and they're also incredibly flexible because of their lack of a skeleton or hard shell, which makes them able to squeeze through tiny spaces. The Greek root, oktopous, means "eight-foot."
Vocabulary lists containing octopus
Marine Biology - Introductory
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Marine Biology - Middle School
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Marine Biology - High School
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Scientists thought the fossil showed eight arms, fins and other features typical of an octopus.
From BBC • Apr. 8, 2026
The fossil, known as Pohlsepia mazonensis, is not an octopus.
From Science Daily • Apr. 7, 2026
Senescence is part of the natural life cycle of a female octopus.
From Los Angeles Times • Mar. 26, 2026
"It's been business as usual for us, we stay calm," said the smiling waitress, an octopus tattoo curling up her forearm.
From Barron's • Mar. 10, 2026
The ocean is a fine place to live for an octopus.
From "The Benefits of Being an Octopus" by Ann Braden
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.