cephalothorax
noun
ceph·a·lo·tho·rax
ˌse-fə-lə-ˈthȯr-ˌaks 
: the united head and thorax of an arachnid or higher crustacean
Examples of cephalothorax in a Sentence
Recent Examples on the Web
Their ridged cephalothorax, four pairs of legs and sharp mouth-parts may be seen.
—
Rebecca Kreston, Discover Magazine, 18 Apr. 2011
Opillonids, also called harvestmen, consist of one basic body segment — plus legs — while spiders have two main body parts: the cephalothorax and abdomen.
—Fox News, 3 Jan. 2014
During the molting process, tarantulas contract their abdomens, which pushes fluid into the upper body, or cephalothorax.
—National Geographic, 24 May 2017
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Rebecca Kreston, Discover Magazine, 18 Apr. 2011
Opillonids, also called harvestmen, consist of one basic body segment — plus legs — while spiders have two main body parts: the cephalothorax and abdomen.
—Fox News, 3 Jan. 2014
During the molting process, tarantulas contract their abdomens, which pushes fluid into the upper body, or cephalothorax.
—National Geographic, 24 May 2017
Cite this Entry
“Cephalothorax.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cephalothorax. Accessed 22 Jul. 2025.
Copy CitationKids Definition
cephalothorax
noun
ceph·a·lo·tho·rax
ˌsef-ə-lə-ˈthō(ə)r-ˌaks
-ˈthȯ(ə)r-
: a combined head and thorax (as of a spider or crab)
Medical Definition
cephalothorax
noun
ceph·a·lo·tho·rax
ˌsef-ə-lə-ˈthō(ə)r-ˌaks, -ˈthȯ(ə)r-
: the united head and thorax of an arachnid or higher crustacean
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