In a manner that shows difference or lack of resemblance; in ways that are unlike or not similar.
From Latin dissimilaris plus the English adverbial suffix -ly. The -ly suffix transforms the adjective dissimilar into an adverb describing how an action occurs or a state exists. This adverbial form emerged in Middle English to modify other words.
When you say twins develop dissimilarly despite identical DNA, you're highlighting something fascinating: epigenetics and environment can make genetically identical organisms develop very differently—a concept that puzzled scientists until recently.
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