The quality or state of being dreamy; a distant, abstracted, or imaginative disposition.
From dream + -i (vowel helper) + -ness (abstract noun suffix). The -ness suffix creates an abstract noun expressing the quality of being dreamy.
Dreaminess is the standard English word for this concept, preferred over 'dreamfulness' because it's shorter and the -i- eases pronunciation—this shows how English speakers gradually selected for the smoothest-sounding words over perfectly logical alternatives.
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