Frustrate

Part of speech: verb (v.)

1. To bring to nothing; to prevent from attaining a purpose; to disappoint; to defeat; to baffle; as, to frustrate a plan, design, or attempt; to frustrate the will or purpose. Shall the adversary thus obtain His end and frustrate thine Milton.

2. To make null; to nullifly; to render invalid or of no effect; as, to frustrate a conveyance or deed.

Synonyms: balk; thwart; foil; baffle; defeat.

Part of speech: adjective (a.)

Vain; ineffectual; useless; unprofitable; null; voil; nugatory; of no effect. "Our frustrate search." Shak.