posterior

American  

[po-steer-ee-er, poh-] / pɒˈstɪər i ər, poʊ- /

adjective

1. situated behind or at the rear of; hinder (opposed to anterior).

2. coming after in order, as in a series.

3. coming after in time; later; subsequent (sometimes followed byto ).

4. Anatomy, Zoology.

   1. (in quadrupeds) pertaining to or toward the rear or caudal end of the body.

   2. (in humans and other primates) pertaining to or toward the back plane of the body, equivalent to the dorsal surface of quadrupeds.

5. Botany. toward the back and near the main axis, as the upper lip of a flower.

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noun

• posteriors
  plural

1. the hinder parts or rump of the body; buttocks.

posterior British  

/ pɒˈstɪərɪə /

adjective

1. situated at the back of or behind something

2. coming after or following another in a series

3. coming after in time

4. zoology (of animals) of or near the hind end

5. botany (of a flower) situated nearest to the main stem

6. anatomy dorsal or towards the spine

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noun

1. the buttocks; rump

2. statistics a posterior probability

Synonym Usage

See back ¹.

Other Word Forms

Derived Forms

• posteriorly
  adverb

Inflected Forms

Nouns

• posteriors
  plural

Etymology

Origin of posterior

1525–35; < Latin, comparative of posterus coming after, derivative of post after

Explanation

Use the adjective posterior to describe something that's in the back. It’s often used in anatomy — a posterior cerebral artery supplies blood to the back of the brain, and the tail is on the posterior of a fish. The prefix post means “after,” and things that are posterior come after the things in the front. The opposite of posterior is anterior, which refers to the front, usually of body parts. You can also use the word posterior to jokingly refer to the part of your body that you sit on — your backside. Posterior is also a formal way to say later in time.

Example Sentences

See Examples For:

posterior posteriors

"The depression and the anxiety I've had from this stupid decision to try and alter my posterior, it just wasn't worth it," she said.

From BBC ● Feb. 23, 2026

To offset that, he pays extra attention to strengthening the posterior, or back, chain of their bodies.

From Los Angeles Times ● Jan. 1, 2026

Research has shown that the premotor and posterior parietal cortices, along with the temporoparietal junction, are active in the brain when we are locating or thinking about ourselves.

From Salon ● May 26, 2025

Dyeing poison frogs, Dendrobates tinctorius, have been shown to tap their posterior toes in response to a range of prey sizes, from small fruit flies to large crickets.

From Science Daily ● May 28, 2024

“At the occipital bone, the posterior base of my skull,” Rachael said.

From "Do Androids Dream of Electric Sheep?" by Philip K. Dick

It's not just about red boxes and posteriors on the seats of government cars.

From BBC ● Jun. 27, 2026

Today, those same simulated posteriors are essential to making sure new sensors are in good working order.

From The Wall Street Journal ● Feb. 20, 2026

Radke examines the bustle, popularized in 1868, a rare historic moment when women opted to increase the appearance of their posteriors to “create the desired gluteal lump.”

From Washington Post ● Nov. 25, 2022

The legion resulting posteriors may protrude into the seawater through natural holes in the sponge and amble along its surface.

From Scientific American ● Aug. 8, 2021

I wonder if he was a relation of the Carters of Portsmouth, because if he is, his posteriors have greatly degenerated in size and figure.

From Harper's New Monthly Magazine, vol 1-98, 1850-1899 None by Various (magazine) Harper

Related Words

• backside
• derriere
• fanny
• rear end
• rump