thorax

noun

tho·​rax ˈthȯr-ˌaks How to pronounce thorax (audio)
plural thoraxes or thoraces ˈthȯr-ə-ˌsēz How to pronounce thorax (audio)
1
: the part of the vertebrate body between the neck and the abdomen
If you count the vertebrae in the necks and thoraxes of mice and chickens, you will find that a mouse has seven neck and 13 thoracic vertebrae, a chicken 14 and seven, respectively.Matt Ridley
also : thoracic cavity
The thorax is evaluated for fluid at the flanks and for pneumothorax anteriorly. Christoper L. Moore
2
: the middle of the three chief divisions of the body of an insect
Of nearly a million described species of insects, none has a biramous appendage, and nearly all have exactly three pairs of limbs on the thorax.Stephen Jay Gould
This haunting pitch issues from drum tissue stretched over the thorax of the male annual cicada …Ted Williams
also : the corresponding part of a crustacean or an arachnid
The brown recluse spider … is brown and has fuzzy body hair and a dark violin- or pear-shaped band on the dorsum of its thorax. Peter F. Weller

Examples of thorax in a Sentence

Recent Examples on the Web If an infected wound is identified, the ants then treat said wound with antibiotics produced by a special gland on the side of the thorax (the metapleural gland). Jennifer Ouellette, Ars Technica, 2 July 2024 Black with bright yellow legs, the flying insect would hover at the hive entrance, capture a flying honeybee and butcher it before darting off with the bee’s thorax, the meatiest bit. Hannah Hoag, USA TODAY, 28 May 2024 The heart gets not one but two bags: a tough outer fibrous pericardium and a serous pericardium, protecting the heart and fixing it firmly in place in our constantly moving thorax. Bethany Brookshire, Scientific American, 27 Dec. 2023 While many beetles may look similar, Japanese beetles are known for their metallic green thoraxes, the section of the body between the head and abdomen, according to the California Department of Food and Agriculture. Hanh Truong, Sacramento Bee, 7 June 2024 See all Example Sentences for thorax 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'thorax.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Middle English, from Latin thorac-, thorax breastplate, thorax, from Greek thōrak-, thōrax

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of thorax was in the 15th century

Dictionary Entries Near thorax

Cite this Entry

“Thorax.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thorax. Accessed 22 Jul. 2024.

Kids Definition

thorax

noun
tho·​rax ˈthō(ə)r-ˌaks How to pronounce thorax (audio)
ˈthȯ(ə)r-
plural thoraxes or thoraces ˈthōr-ə-ˌsēz How to pronounce thorax (audio)
ˈthȯr-
1
: the part of the body of a mammal between the neck and the abdomen
also : its cavity in which the heart and lungs lie
2
: the middle of the three main divisions of the body of an insect

Medical Definition

thorax

noun
plural thoraxes or thoraces ˈthōr-ə-ˌsēz, ˈthȯr- How to pronounce thorax (audio)
1
a
: the part of the body in vertebrates that is situated between the neck and the abdomen and supported by the ribs, costal cartilages, and sternum
2
: the middle of the three chief divisions of the body of an insect
also : the corresponding part of a crustacean or an arachnid
Last Updated: - Updated example sentences
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