The quality or state of being cumbersome; bulkiness, awkwardness, or the degree to which something impedes progress.
From 'cumbersome' + '-ness' (abstract noun suffix). The '-ness' ending converts adjectives into abstract nouns describing qualities or conditions.
The '-ness' suffix is one of English's favorite tricks for turning feelings or qualities into nouns—'happy' becomes 'happiness,' 'kind' becomes 'kindness,' so 'cumbersome' becomes 'cumbersomeness,' the abstract noun for heaviness and awkwardness.
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