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.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

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
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

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]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

arachnoid

A web-like membrane: the middle of the three meninges covering the brain and spinal cord.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
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
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
Translations

a·rach·noid

n. aracnoides, membrana media cerebral que cubre el cerebro y la médula espinal.
English-Spanish Medical Dictionary © Farlex 2012
References in periodicals archive ?
Unique in design, the Microsurgical instrument portfolio offers highly-specialised solutions for neurosurgeons, including blades designed for cutting Dura Mater and Arachnoid Membrane, in addition to other brain tissues.
All the laminectomy sections were evaluated for fibrosis density and arachnoid involvement by a single pathologist who was blind to the study groups.
However, these structures can be seen through endoscopic surgery of suprasellar arachnoid cysts (SSCs) due to their proximity to the pituitary gland.
Emerson Grant, from Oatlands,Weybridge, has an arachnoid cyst which means he cannot move from the waist down, despite multiple surgeries to try and remove it.
The meninges are composed of three layers: the Pia mater, Arachnoid mater and the Dura mater; all are contiguous with their cranial counterparts.
The medical examination revealed that he suffered from 'heat stroke vs sub arachnoid hemorrhage' and the cause of death was later confirmed to be hypoxic-ischemic encephalopathy or brain injury due to asphyxia caused by reduced blood flow to the brain.
A CT scan was interpreted as interhemispheric arachnoid cyst.
There were no neural elements herniating into the sacs, and the walls were sent for histology which demonstrated arachnoid enmeshed in a fibrous capsule.
Meningiomas are slow-growing, relatively common tumors arising from arachnoid cap cells of the meninges and constitute 13-18% of adult intracranial neoplasms.
The cerebral veins coursing beneath deep surface of arachnoid matter are further drain to the nearest dural venous sinuses.
The defendant caused a small dural tear with subsequent laceration of the arachnoid, resulting in a leak of cerebrospinal fluid.