Sentence:  Thus, by the Ratio Test, the <WSD>binomial series</WSD> converges if |x| < 1 and diverges if |x| > 1. 
Meaning of the word marked with <WSD> tags:  The Maclaurin series expansion of the function "f"("x")  = (1 + "x")"α", for arbitrary complex "α"; the series \textstyle\sum_{k=0}^\infty{\alpha \choose k} x^k, where \textstyle{\alpha \choose k} = \frac{\alpha(\alpha-1)(\alpha-2)·s(\alpha-k+1)}{k!}.