arachnoid


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a·rach·noid

 (ə-răk′noid′)
adj.
1. Anatomy Of or relating to a delicate membrane enclosing the spinal cord and brain.
2. Of, relating to, or resembling arachnids.
3. Covered with or consisting of thin, soft, entangled hairs or fibers resembling those of a cobweb or spider's web.
n.
1. An arachnid.
2. Anatomy A delicate membrane that encloses the spinal cord and brain and lies between the pia mater and dura mater.

[New Latin arachnoīdēs, from Greek arakhnoeidēs, cobweblike : arakhnē, spider + -oeidēs, -oid.]

arachnoid

(əˈræknɔɪd)
n
1. (Anatomy) the middle of the three membranes that cover the brain and spinal cord. See meninges
2. (Zoology) another name for arachnid
adj
3. (Anatomy) of or relating to the middle of the three meninges
4. (Botany) botany consisting of or covered with soft fine hairs or fibres
5. (Zoology) of or relating to the arachnids

a•rach•noid

(əˈræk nɔɪd)

adj.
1. of or belonging to the arachnids.
2. of or pertaining to the arachnoid.
3. Bot. formed of or covered with long, delicate hairs or fibers.
n.
4. the serous membrane forming the middle of the three coverings of the brain and spinal cord. Compare dura mater, meninges, pia mater.
[1745–55; < New Latin arachnoīdes < Greek arachnoeidḗs cobweblike. See arachnid, -oid]

arachnoid

A web-like membrane: the middle of the three meninges covering the brain and spinal cord.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.arachnoid - the middle of the 3 meninges
meninges, meninx - a membrane (one of 3) that envelops the brain and spinal cord
leptomeninges - the two innermost layers of the meninges; cerebrospinal fluid circulates between these innermost layers
2.arachnoid - air-breathing arthropods characterized by simple eyes and four pairs of legsarachnoid - 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
false scorpion, pseudoscorpion - small nonvenomous arachnid resembling a tailless scorpion
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
Adj.1.arachnoid - relating to or resembling a member of the class Arachnidaarachnoid - relating to or resembling a member of the class Arachnida
zoological science, zoology - the branch of biology that studies animals
Translations

a·rach·noid

n. aracnoides, membrana media cerebral que cubre el cerebro y la médula espinal.
References in periodicals archive ?
Postmortem examinations demonstrated an arachnoid cyst, corpus callosum agenesis and left diaphragmatic hernia.
Lauren Pritchard was clearing out a cupboard in her kitchen when she discovered the 50p sized arachnoid lurking inside.
Table 1: Aetiological factors for dysphagia Diagnostic Group Example Neurological Stroke Sub Arachnoid Haemorrhage Multiple Sclerosis Motor Neuron Disease Brain tumour Traumatic Brain Injury Encephalitis Post Polio Syndrome Developmental problems (Cleft palate) Musculoskeletal Cervical Osteophytes Spondylolisthesis Rheumatoid arthritis Disc Prolapse Malignancy Tongue Gum Larynx Pharynx Oesophagus Infection Candida Streptococcal Cardio respiratory Heart Failure COPD Lung Fibrosis Iatrogenic Post intubation Post surgery Other Pharyngeal pouch Pharyngeal atresia/stenosis Cricopharyngeal spasm Oesophageal atresia Oesophageal achalasia Frailty Medication Anticholinergic medication Antibiotics Opiates Anti psychotics Benzodiazepines Calcium Channel Blockers Self Harm Bleach Fire
However, autoinflammatory mediated injury within the arachnoid villi and the resultant decrease in cerebrospinal fluid absorption and/or thrombotic, vasculitic obliteration of cerebral arteriolar and venous systems are among the most probable mechanisms.
Giant arachnoid granulation mimicking dural sinus thrombosis in a boy with headache: MRI.
Communicating hydrocephalus may result due to occlusion of basilar cisterns by inflammatory exudate and/or fibrosis preventing CSF from being absorbed by arachnoid granulations or non-communicating hydrocephalus may result from obstruction at the level of the outlet foramina of the fourth ventricle (27) (Figure 11).
Meningiomas are usually benign, slow-growing tumors that originate from arachnoid cap cells (1).
5% + 8% dextrose anhydrous, sub arachnoid, blister / road or bulb 5mg / ml 4ml.
Most adult mites possess the usual arachnoid appendages, jaws, palps at the front end, and four pairs of legs.
These features were highly suggestive of an Echinococcus cyst, with differential diagnosis of cysticercosis, cystic neoplasm such as schwannoma, and arachnoid cyst.
I may as well get a job repossessing houses, so heartless am I to the arachnoid community, bulldozing their bricks and mortar.
A 7 mm incision to a rabbit's inferior vena cava can be fatal, but by applying nanosheets to the bleeding area, we succeeded in quick hemostasis in all the rabbits (wounds to the lungs, digestive tract and the brain's arachnoid membrane can also be simply covered by applying nanosheets).