posterior

1 of 2

adjective

pos·​te·​ri·​or pō-ˈstir-ē-ər 

pä-

1

: later in time : subsequent

2

: situated behind: such as

a

: caudal

b

of the human body or its parts : dorsal

3

of a plant part : adaxial, superior

posteriorly adverb

posterior

2 of 2

noun

pos·​te·​ri·​or pä-ˈstir-ē-ər 

pō-

: the hinder parts of the body

specifically : buttocks

Did you know?

Posterior comes from the Latin word posterus, meaning "coming after". Posterior is often used as a technical term in biology and medicine to refer to the back side of things, and is the opposite of anterior, which refers to the front side. For example, as more people took up running as a sport, doctors began to see an increase in stress fractures along the posterior as well as the anterior surface of the lower leg bones. In some technical fields, posterior may mean "later". When used as a noun, posterior simply means "buttocks".

Synonyms

Adjective

• rear
• back
• hind

Noun

• cheeks
• tail
• seat
• bum
• rump
• rear

Examples of posterior in a Sentence

Adjective

the posterior part of the brain

the chapel's posterior location in the church serves to make it a quiet retreat

Noun

The man squeezed his large posterior into the chair.

the baseball players were always slapping one another on the posterior

Recent Examples on the Web

Adjective

Wrapping around your neck, the cushion comes up over the ears and around the front, offering 360-degree posterior, lateral, and chin support. —Olivia Young, Travel + Leisure, 1 July 2025

The posterior tibial artery on the inner ankle. Find a pulse point on your body and apply a cold compress or ice pack to one or all of them for 10-15 minutes. —Maryal Miller Carter, USA Today, 20 June 2025

Noun

Those who just want to dangle their legs and keep their posteriors affixed for the entire run, though, can still see through the clear water, especially when migrating over to pockets of shade from the trees lining either bank. —Richard Tribou, The Orlando Sentinel, 31 May 2025

Lacking muscle One possibility here is that wnt signaling is widely active in the posterior of the embryo at this point, blocking formation of anterior structures. —John Timmer, ArsTechnica, 18 Apr. 2025

Word History

Etymology

Adjective

Latin, comparative of posterus coming after, from post after — more at post-

First Known Use

Adjective

1534, in the meaning defined at sense 1

Noun

1605, in the meaning defined above

Phrases Containing posterior

• posterior chamber
• posterior cruciate ligament

Rhymes for posterior

• anteroposterior

Kids Definition

posterior

1 of 2 adjective

pos·​te·​ri·​or pō-ˈstir-ē-ər 

pä-

1

: later in time : subsequent

2

: located behind or toward the back

posteriorly adverb

posterior

2 of 2 noun

pos·​te·​ri·​or pä-ˈstir-ē-ər 

pō-

: the hind end of the body

especially : buttock sense 2a

Medical Definition

posterior

1 of 2 adjective

pos·​te·​ri·​or pō-ˈstir-ē-ər, pä- 

: situated behind: as

a

: situated at or toward the hind part of the body : caudal

b

: dorsal

—used of human anatomy in which the upright posture makes dorsal and caudal identical

posterior

2 of 2 noun

pos·​te·​ri·​or pä-ˈstir-ē-ər, pō- 

: a posterior thing or part: as

a

: the rear end of a quadruped

b

: buttocks