Without furniture; empty of furnishings or lacking the equipment and fixtures that would typically fill a space.
From furniture + -less (Old English suffix meaning 'without' or 'lacking'), following the standard English pattern of negating nouns with -less.
The -less suffix is brilliant for creating opposites instantly—any English speaker can understand 'furnitureless' even if they've never heard it before, which shows how living languages let us build meaning on the fly.
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