In a manner lacking symmetry or balanced proportion; asymmetrically.
From dissymmetrical + -ly (adverb suffix). This adverb form allows the concept to modify verbs, adjectives, or other adverbs in sentences.
The -ly adverb suffix is so old and productive in English that you can almost always add it to an adjective to create the matching adverb—it's one of the most predictable grammar patterns, dating back to Old English.
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