Early 19th century; earliest use found in Robert Jameson (1774–1854), geologist and natural historian. Either from geognostic + -ally, or from geognostical + -ly.
Definition of geognostically in US English:
geognostically
adverb
rare, historical
As regards or with reference to geognosy.
Origin
Early 19th century; earliest use found in Robert Jameson (1774–1854), geologist and natural historian. Either from geognostic + -ally, or from geognostical + -ly.