In*an"i*ty (?), n.; pl. Inanities (#). [L. inanitas, fr. inanis empty: cf. F. inanit'e. See Inane.]
1.
Inanition; void space; vacuity; emptiness.
2.
Want of seriousness; aimlessness; frivolity.
3.
An inane, useless thing or pursuit; a vanity; a silly object; -- chiefly in pl.; as, the inanities of the world.
© Webster 1913.