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“geomagnetic variation”
Any change that happens to the geomagnetic field: A geomagnetic variation can be temporal or short-time changes in the geomagnetic field, both long-term (secular) and short-term (transient).
This entry is located in the following units:
-ation, -ization (-iz[e] + -ation); -isation (British spelling variation)
(page 45)
geo-, ge- +
(page 14)
vari-
(page 1)