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1

arachnoid

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adjective arach·noid \ə-ˈrak-ˌnȯid\

Definition of arachnoid

  1. 1 :  of or relating to a thin membrane of the brain and spinal cord that lies between the dura mater and the pia mater

  2. 2 :  covered with or composed of soft loose hairs or fibers




2

arachnoid

noun arach·noid

Definition of arachnoid

  1. :  an arachnoid membrane



Origin of arachnoid

New Latin arachnoides, from Greek arachnoeidēs, like a cobweb, from arachnē spiderweb


First Known Use: 1804


3

arachnoid

adjective arach·noid

Definition of arachnoid

  1. :  resembling or related to the arachnids



Origin of arachnoid

New Latin Arachnida + English -oid


First Known Use: 1825


Learn More about arachnoid

  1. Medical Dictionary: Definition of "arachnoid"


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