California Code, Code of Civil Procedure - CCP § 1032

(1) “Complaint” includes a cross-complaint.

(2) “Defendant” includes a cross-defendant, a person against whom a complaint is filed, or a party who files an answer in intervention.

(3) “Plaintiff” includes a cross-complainant or a party who files a complaint in intervention.

(4) “Prevailing party” includes the party with a net monetary recovery, a defendant in whose favor a dismissal is entered, a defendant where neither plaintiff nor defendant obtains any relief, and a defendant as against those plaintiffs who do not recover any relief against that defendant.If any party recovers other than monetary relief and in situations other than as specified, the “prevailing party” shall be as determined by the court, and under those circumstances, the court, in its discretion, may allow costs or not and, if allowed, may apportion costs between the parties on the same or adverse sides pursuant to rules adopted under Section 1034.