Laches

A legal defense to a claim for equitable relief asserting that the plaintiff's long delay in bringing the claim has prejudiced the defendant (as a sort of legal ambush). For example, if a homeowner watches while the neighbor builds a house over their property line, and only then brings a suit to have the house removed, the encroaching neighbor may raise the defense of laches. Don't confuse laches with "statutes of limitations," which set forth specific periods of time within which plaintiffs must file certain types of lawsuits.