Periosteum

noun

noun ·Rare ·Advanced level

Definitions

Noun
  1. 1
    A membrane surrounding a bone.

    "Periosteum and endosteum are connective tissue sheaths of bone. […] The periosteum is a layer of connective tissue covering the external surface of a bone. The periosteum may be divided into two components: / a. An outer fibrous layer consists of dense irregular connective tissue. / b. An inner cellular layer consists of osteoprogenitor (osteogenic) cells."

  2. 2
    a dense fibrous membrane covering the surface of bones (except at their extremities) and serving as an attachment for tendons and muscles; contains nerves and blood vessels that nourish the enclosed bone wordnet

Example

More examples

"Periosteum and endosteum are connective tissue sheaths of bone. […] The periosteum is a layer of connective tissue covering the external surface of a bone. The periosteum may be divided into two components: / a. An outer fibrous layer consists of dense irregular connective tissue. / b. An inner cellular layer consists of osteoprogenitor (osteogenic) cells."

Etymology

From Ancient Greek περί (perí, “about, around”) + ὀστέον (ostéon, “bone”).

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.