In a craggy manner; in a way that is rough, rocky, or jagged.
From 'craggy' plus the adverbial suffix '-ly,' which converts adjectives into adverbs. The base word 'crag' dates to Middle English with possible Scandinavian origins.
Adverbs ending in '-ly' are one of the most productive word formations in English, but 'craggily' is relatively rare because we don't often need to describe things happening in a rocky way—which makes it a delightfully specific word for creative writers.
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