1. A layer of myelin encasing (and insulating) the axons of medullated nerve fibers
   - myelin sheath

Derived forms: medullary sheaths

Type of: case, sheath

Part of: medullated nerve fiber [US], medullated nerve fibre [Brit, Cdn], myelinated nerve fiber [US], myelinated nerve fibre [Brit, Cdn]

Encyclopedia: Medullary sheath

• backscatter
• backscratcher
• backseat
• backseat driver
• backsheesh
• backside
• backslap
• backslapper
• backslash
• backslide
• backslider
• backsliding
• backspace
• backspace character
• backspace key
• backspacer
• backspin
• backstabber
• backstage
• backstair
• backstairs
• backstay
• backstitch
• backstop
• backstory