English
magnetosheath
From magneto- + sheath.
A compound of magneto- + sheath
Proto-Indo-European *skey- ‘to dissect, split’
Proto-Germanic *skaiþiz
Proto-West Germanic *skaiþiju
Old English sċēaþ
Middle English sheth ‘holder for a sword, knife, etc., scabbard,…’
English sheath
Today it means
noun The region of space between the magnetopause and the bow shock of a planet's magnetosphere
Language periods are conventional ranges, not dates for this word.
Etymograph / magnetosheath