The quality or state of being unlike or dissimilar; lack of resemblance or similarity.
From 'dislike' or 'dis-' + 'likeness' (from 'like' + '-ness' suffix, from Old English '-nis', forming abstract nouns). Alternatively from 'disliken' + '-ness'.
The '-ness' suffix is one of English's most productive tools for creating nouns from adjectives—'dislikeness' parallels words like 'sadness' and 'happiness', though it's rarely used because 'difference' or 'dissimilarity' are more common.
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