pericranium
noun
peri·cra·ni·um ˌper-ə-ˈkrā-nē-əm 
plural pericrania ˌper-ə-ˈkrā-nē-ə
: the external periosteum of the skull
pericranial
ˌper-ə-ˈkrā-nē-əl
adjective 
Word History
Etymology
Middle English pericraneum, from Medieval Latin, from Greek perikranion, neuter of perikranios around the skull, from peri- + kranion skull — more at cranium
First Known Use
15th century, in the meaning defined above
Medical Definition
pericranium
noun
peri·cra·ni·um ˌper-ə-ˈkrā-nē-əm
plural pericrania -nē-ə
: the external periosteum of the skull