In mathematics, a quippian is a degree 5 class 3 contravariant of a plane cubic introduced by Arthur Cayley (1857) and discussed by Igor Dolgachev (2012, p.157). In the same paper Cayley also introduced another similar invariant that he called the pippian, now called the Cayleyan.

• Glossary of classical algebraic geometry

• Cayley, Arthur (1857), "A Memoir on Curves of the Third Order", Philosophical Transactions of the Royal Society of London, 147, The Royal Society: 415–446, doi:10.1098/rstl.1857.0021, ISSN 0080-4614, JSTOR 108626
• Dolgachev, Igor V. (2012), Classical Algebraic Geometry: a modern view (PDF), Cambridge University Press, ISBN 978-1-107-01765-8