Ceremonial deism is a legal term used in the United States to designate governmental religious references and practices deemed to be mere cultural rituals and not inherently religious because of long customary usage. Proposed examples of ceremonial deism include the reference to God introduced into the Pledge of Allegiance in 1954, the phrase "In God We Trust" on U.S. currency, and the Ohio state motto, "With God, all things are possible".
The term was coined in 1962 by the then-dean of Yale Law School, Eugene Rostow, and has been used since 1984 by the Supreme Court of the United States to assess exemptions from the Establishment Clause of the First Amendment to the U.S. Constitution.