Lying under oath in a court of law is termed Perjury. It is a criminal offense involving knowingly making false statements after swearing to tell the truth, typically in judicial proceedings. Perjury undermines the integrity of the legal system and can lead to wrongful convictions or acquittals. Unlike forgery, which involves falsifying documents, perjury specifically relates to verbal or written false testimony under oath. Recognizing perjury is critical in maintaining justice and accountability within the court.

Reference: Medical Jurisprudence, Ratan K. Chaurasia, 5th Edition.