"Vapid"

When:

Lookups on Merriam-Webster started spiking on June 29, 2010.

Why:

As the hearings began for Supreme Court nominee Elena Kagan, many media reports included Kagan's own thoughts on the process, revealed in a book review she wrote in 1995:

"Subsequent hearings have presented to the public a vapid and hollow charade, in which repetition of platitudes has replaced discussion of viewpoints and personal anecdotes have supplanted legal analysis."

Vapid means "lacking liveliness, tang, briskness, or force: flat or dull."

It comes from a Latin word meaning "flat-tasting."