1

arachnoid

adjective arach·noid \ ə-ˈrak-ˌnȯid \

Definition of arachnoid

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 : covered with or composed of soft loose hairs or fibers

First Known Use of arachnoid

1789

in the meaning defined at sense 1

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2

arachnoid

noun

Definition of arachnoid

: an arachnoid membrane

Origin and Etymology of arachnoid

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


3

arachnoid

adjective

Definition of arachnoid

: resembling or related to the arachnids

Origin and Etymology of arachnoid

New Latin Arachnida + English -oid


Medical Dictionary

1

arachnoid

noun arach·noid \ ə-ˈrak-ˌnȯid \

medical Definition of arachnoid

: a thin membrane of the brain and spinal cord that lies between the dura mater and the pia mater

2

arachnoid

adjective
variants: also arachnoidal play \ə-ˌrak-ˈnȯid-ᵊl\

medical Definition of arachnoid

: of or relating to the arachnoid
  • the arachnoid membrane

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