In mathematics, the Taylor series or Taylor expansion of a function is an infinite sum of terms that are expressed in terms of the function's derivatives at a single point. Wikipedia

Infinite series of polynomials which asymptotically approaches infinitely differentiable functions Wikipedia Disambiguation

Expression of a function as an infinite sum Wikidata

A power series representation of given infinitely differentiable function f whose terms are calculated from the function's arbitrary order derivatives at given reference point a ; the series f ( a ) + f ′ ( a ) 1 ! ( x − a ) + f ″ ( a ) 2 ! ( x − a ) 2 + f ‴ ( a ) 3 ! ( x − a ) 3 + ⋯ = ∑ n = 0 ∞ f ( n ) ( a ) n ! ( x − a ) n . Wiktionary

Power series of a function calculated from derivatives at a reference point. Wiktionary (translation)