The quality or state of producing or being filled with fumes; smokiness.
From Latin 'fumiditas' (smokiness, from fumidus), using the common Latin suffix '-ity' to convert the adjective into an abstract noun describing the quality itself.
Fumidity is parallel to 'humidity' (from Latin 'humidus', moist)—both words use similar Latin patterns, but 'humidity' survives in modern English while 'fumidity' has become obsolete, showing which concepts matter to modern speakers.
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