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

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

Brown: Posterior chain is everything up and down the backside of your body and the posterior.

From Los Angeles Times ● Jan. 28, 2025

Dr. Keith Meister performed the surgery in Arlington, Texas, to repair what Hollander described as a small tear in the posterior of Brash’s ulnar collateral ligament.

From Seattle Times ● May 10, 2024

He plumped his large posterior onto the lavatory pan.

From "1984" by George Orwell

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

This from someone who refers to his players’ posteriors as “tails” — as in, “They practiced their tails off this week.”

From Los Angeles Times ● Sep. 15, 2019

“They kicked our ass,” Texas Coach Tom Herman, then the offensive coordinator at Ohio State, recalled this past summer, but they just did not kick it in the way other posteriors have gotten kicked lately.

From Washington Post ● Nov. 12, 2017

I waxed old in misery and disgrace, having only one-half of my posteriors, and always remembering I was a Pope's daughter.

From Candide by Voltaire

Related Words

• backside
• derriere
• fanny
• rear end
• rump