magnetopause

[mag-nee-tuh-pawz] /mægˈni təˌpɔz/
noun, Astronomy
1.
the boundary between the earth's magnetosphere and interplanetary space, about 40,000 miles (65,000 km) above the earth, marked by an abrupt decrease in the earth's magnetic induction.
2.
a similar feature of some other planet.
Origin
1960-65; magneto- + pause
Word Origin and History for magnetopause
n.

1963, from magneto- in magnetosphere + pause (n.).