(6 October 1909 – 23 April 1996) was an Italian Cardinal of the Roman Catholic Church who served as personal theologian to five popes from 1955 to 1989, and was elevated to the cardinalate in 1977.

He later entered the Order of Friars Preachers, more commonly known as the Dominicans, and professed in the convent of Santa Maria della Quercia in Viterbo.

After studying at the convent of San Domenico in Pistoia, he attended the Pontifical University of Saint Thomas Aquinas, Angelicum in Rome, where he obtained his doctorate in theology in 1933 with a thesis entitled De divina misericordia ut prima causa operum Dei.

The title was later renamed as Theologian of the Pontifical Household on 28 March 1968 by Pope Paul VI's motu proprio Pontificalis Domus.

Paul VI, shortly afterwards, created Ciappi Cardinal Deacon of Nostra Signora del Sacro Cuore in the consistory of 27 June 1977.