Perjury is the act of lying under oath. It is a serious offence that can result in severe legal consequences. There are several synonyms for the word perjury that can help to accurately describe the action. False swearing, lying on oath, making false statements, mendacity, deception, deceit, and fabrication are some of the common synonyms. These words can be used interchangeably to describe the deliberate act of lying or providing false information while under oath. The use of synonyms can help to amplify the severity of the act and emphasize the importance of speaking truthfully in legal proceedings.