In a manner relating to the study of Earth's rock composition and internal structure.
From geognostical plus the adverbial suffix -ly, which converts adjectives into adverbs describing how something happens or is done. This common English transformation creates adverbs that describe actions or qualities.
English's -ly suffix is so productive that scientists could instantly create adverbs for any new field—geognostically lets them say 'from the perspective of geognosy' without inventing a whole new word, showing how efficient language can be.
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