Frivolous

Friv"o*lous (?), a. [L. frivolus; prob. akin to friare to rub, crumble, E. friable: cf. F. frivole.]

1. Of little weight or importance; not worth notice; slight; as, a frivolous argument. Swift.

2. Given to trifling; marked with unbecoming levity; silly; interested especially in trifling matters.

His personal tastes were low and frivolous.
Macaulay.

Syn. -- Trifling; trivial; slight; petty; worthless.

-- Friv"o*lous*ly, adv. -- Friv"o*lous*ness, n.