English
magnetotail
From magneto- + tail.
Proto-Indo-European *deḱ- ‘to tear, fray, shred’
…
Proto-Germanic *taglą ‘hair, fiber’
Proto-West Germanic *tagl
Old English tæġel
Middle English tail
English tail
Today it means
noun The long, trailing part of a magnetosphere on the side of a planet furthest from the sun
Language periods are conventional ranges, not dates for this word.
Etymograph / magnetotail