inanity (n.) Look up inanity at Dictionary.com
c. 1600, "emptiness, hollowness," literal and figurative, from French inanité (14c.) or directly from Latin inanitas "emptiness, empty space," figuratively "worthlessness," noun of quality from inanis "empty, void; worthless, useless," a word of uncertain origin. De Vaan writes that "The chronology of attestations suggests that 'empty, devoid of' is older than 'hollow'." Meaning "silliness, want of intelligence" is from 1753.