periosteum
noun
peri·os·te·um ˌper-ē-ˈä-stē-əm 
plural periostea ˌper-ē-ˈä-stē-ə
: the membrane of connective tissue that closely invests all bones except at the articular surfaces
Example Sentences
Recent Examples on the Web Doctors think surfer’s ear happens because the thin skin of the ear canal doesn’t protect the bone from cold water, which causes inflammation in the membrane on the outside of the bone, called the periosteum. 
Kiona N. Smith, Ars Technica, 28 Dec. 2018
Kiona N. Smith, Ars Technica, 28 Dec. 2018 Word History
Etymology
New Latin, from Late Latin periosteon, from Greek, neuter of periosteos around the bone, from peri- + osteon bone — more at osseous
First Known Use
1574, in the meaning defined above
Medical Definition
periosteum
noun
peri·os·te·um -tē-əm
plural periostea -tē-ə
: the membrane of connective tissue that closely invests all bones except at the articular surfaces