Dictionary.com
Thesaurus.com

arachnoid

American  
[uh-rak-noid] / əˈræk nɔɪd /

adjective

  1. resembling a spider's web.

  2. of or belonging to the arachnids.

  3. Anatomy. of or relating to the arachnoid membrane.

  4. Botany. formed of or covered with long, delicate hairs or fibers.


noun

  1. an arachnid.

  2. Anatomy. the serous membrane forming the middle of the three coverings of the brain and spinal cord.

arachnoid British  
/ əˈræknɔɪd /

noun

  1. the middle of the three membranes that cover the brain and spinal cord See meninges

  2. another name for arachnid

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

  1. of or relating to the middle of the three meninges

  2. botany consisting of or covered with soft fine hairs or fibres

  3. of or relating to the arachnids

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
arachnoid Scientific  
/ ə-răknoid′ /
  1. The delicate membrane that encloses the spinal cord and brain and lies between the pia mater and dura mater.


Etymology

Origin of arachnoid

1745–55; < New Latin arachnoīdes < Greek arachnoeidḗs cobweblike. See arachnid, -oid

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Lopez plays dual roles as a movie actor and an arachnoid goddess and she sauntered into the Sundance premiere channeling the power of both.

From Los Angeles Times

Large veins are known to pass through the arachnoid barrier carrying blood away from the brain, and these were clearly observed on the MRI scans.

From Science Daily

The meninges comprise three layers that surround the brain: pia, arachnoid and dura.

From Salon

He stepped down at Ohio State in 2018 mostly because of a congenital arachnoid cyst in his brain, which required surgery in 2014 and bothered him throughout his final season with the Buckeyes.

From Washington Times

The 54-year-old Meyer has an arachnoid cyst in his brain that causes severe headaches, and had shown obvious effects of being in pain on the sideline this season.

From Washington Times