nonsuit

Short definition from Wiktionary

Noun

1. 1
   A lawsuit that is dismissed as having been brought without cause, prior to an adjudication on the merits.
2. 2
   A neglect or failure by the plaintiff to follow up his suit; a renunciation or withdrawal of the cause by the plaintiff.

Verb

1. 1
   To dismiss (a suit or plaintiff) on the grounds of his or her lawsuit having been brought without cause, prior to an adjudication on the merits.