Archaic or alternate spelling of 'dullness'; the quality or state of being dull.
Variant spelling of 'dullness' that was more common before standardization. The single 'l' version reflects older English orthography before the 'double consonant before suffix' rule was formalized.
Spelling wasn't standardized until the 1800s, so old texts show 'dulness,' 'dullness,' and even 'dullnesse'—Shakespeare could spell however he wanted and people understood!
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