The ongoing process of making or becoming dissimilar; currently causing things to become unlike each other.
From the present participle of Latin dissimilare with the -ing suffix. The -ing form creates either a gerund (noun) or a present participle (verb form) describing the action in progress.
When you see dissimilating in action linguistically, it's everywhere—sounds in languages constantly dissimilate to be easier to pronounce, which is why Old English had more similar consonant clusters than modern English does.
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