**Theodore Seio Chihara** (born 1929) is a mathematician working on orthogonal polynomials who introduced Al-Salam–Chihara polynomials, Brenke–Chihara polynomials, and Chihara–Ismail polynomials

Chihara, Theodore Seio (1978), *An introduction to orthogonal polynomials*, Mathematics and its Applications, **13**, New York: Gordon and Breach Science Publishers, ISBN 978-0-677-04150-6, MR 0481884, Reprinted by Dover 2011, ISBN 978-0-486-47929-3
Chihara, Theodore Seio (2001), "Proceedings of the Fifth International Symposium on Orthogonal Polynomials, Special Functions and their Applications (Patras, 1999)", *Journal of Computational and Applied Mathematics*, **133** (1): 13–21, ISSN 0377-0427, MR 1858267, doi:10.1016/S0377-0427(00)00632-4