Chebyshev polynomial

Chebyshev polynomials

(which see!). An article about John, Paul, George, and Ringo would not be titled Beatle, but Beatles or The Beatles. So it is here. One does speak of a "Chebyshev polynomial" in the singular in some contexts, but generally those are of interest only because this polynomial sequence, like others, is thought of as a unit. If a link brought you to this page, it should be fixed so that although the text says "Chebyshev polynomial", in the singular, the page it points to is "Chebyshev polynomials" (the plural).