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Any of various arthropods of the class Arachnida, such as spiders, scorpions, mites, and ticks, characterized by four pairs of segmented legs and a body that is divided into two regions, the cephalothorax and the abdomen.
[From New Latin Arachnida, class name, from Greek arakhnē, spider.]
a·rach′ni·dan (-nĭ-dən) adj. & n.
(Zoology) any terrestrial chelicerate arthropod of the class Arachnida, characterized by simple eyes and four pairs of legs. The group includes the spiders, scorpions, ticks, mites, and harvestmen
[C19: from New Latin Arachnida, from Greek arakhnē spider]
aˈrachnidan adj, n
any of numerous wingless, carnivorous arthropods of the class Arachnida, comprising spiders, scorpions, mites, and ticks, characterized by a two-segmented body with eight appendages and no antennae.
[1865–70; < New Latin Arachnida < Greek aráchn(ē) spider, spider's web + New Latin -ida -ida]
a•rach′ni•dan, adj., n.
Any of a group of arthropods having eight segmented legs, no wings or antennae, and a body divided into two parts. One part consists of the head and thorax joined together, and the other part is the abdomen. Spiders, mites, scorpions, and ticks are arachnids.
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|Noun||1.||arachnid - air-breathing arthropods characterized by simple eyes and four pairs of legs|
arthropod - invertebrate having jointed limbs and a segmented body with an exoskeleton made of chitin
Arachnida, class Arachnida - a large class of arthropods including spiders and ticks and scorpions and daddy longlegs; have four pairs of walking legs and no wings
harvestman, Phalangium opilio, daddy longlegs - spiderlike arachnid with a small rounded body and very long thin legs
scorpion - arachnid of warm dry regions having a long segmented tail ending in a venomous stinger
whip scorpion, whip-scorpion - nonvenomous arachnid that resembles a scorpion and that has a long thin tail without a stinger
spider - predatory arachnid with eight legs, two poison fangs, two feelers, and usually two silk-spinning organs at the back end of the body; they spin silk to make cocoons for eggs or traps for prey
acarine - mite or tick