The quality or state of being addled; confusion, muddledness, or foolishness.
From 'addle' plus the suffix '-ness,' a common English way to form abstract nouns describing states or qualities.
'-Ness' is the most everyday way to describe a state, while '-ment' is more formal—'addleness' is how a friend might describe someone's confusion, while 'addlement' is how a doctor would write it.
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