thorax
noun
tho·rax
ˈthȯr-ˌaks 
plural thoraxes or thoraces
ˈthȯr-ə-ˌsēz
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
Matt Ridley
also
: thoracic cavity
The thorax is evaluated for fluid at the flanks and for pneumothorax anteriorly. —Christoper L. Moore
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
Stephen Jay GouldThis haunting pitch issues from drum tissue stretched over the thorax of the male annual cicada …—Ted Williams
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
Peter F. Weller Examples of thorax in a Sentence
Recent Examples on the Web
Insects have three body segments (head, thorax, and abdomen) and six legs (three pairs), while spiders have two body segments (cephalothorax and abdomen) and eight legs (four pairs).
—Jake Parks, Discover Magazine, 14 Oct. 2024
The crowning touch is a giant mosquito with a lava lamp on its thorax; the whole thing is made of a bunch of dumb American junk.
—Emily Watlington, ARTnews.com, 10 Sep. 2024
Unlike bees, which are typically fatter and fuzzier, wasps have a distinctive hourglass shape with a very thin waist where the thorax and abdomen meet.
—Tiffany Acosta, The Arizona Republic, 16 Aug. 2024
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
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Jake Parks, Discover Magazine, 14 Oct. 2024
The crowning touch is a giant mosquito with a lava lamp on its thorax; the whole thing is made of a bunch of dumb American junk.
—Emily Watlington, ARTnews.com, 10 Sep. 2024
Unlike bees, which are typically fatter and fuzzier, wasps have a distinctive hourglass shape with a very thin waist where the thorax and abdomen meet.
—Tiffany Acosta, The Arizona Republic, 16 Aug. 2024
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
See all Example Sentences for thorax
Dictionary Entries Near thorax
Cite this Entry
“Thorax.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thorax. Accessed 1 Dec. 2024.
Copy CitationKids Definition
thorax
noun
tho·rax
ˈthō(ə)r-ˌaks
ˈthȯ(ə)r-
plural thoraxes or thoraces
ˈthōr-ə-ˌsēz
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
tho·rax
ˈthō(ə)r-ˌaks, ˈthȯ(ə)r-
plural thoraxes or thoraces
ˈthōr-ə-ˌsēz, ˈthȯr-
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
b
2
: the middle of the three chief divisions of the body of an insect
also
: the corresponding part of a crustacean or an arachnid
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