A characterization of defectless extensions of a Henselian valued field

Let (K; v) be a Henselian valued field of arbitrary rank. A finite extension (K0; v0) of (K; v) is said to be defectless if [K0 : K] = e f , where e and f are, respectively, the ramification index and the residual degree of (K0; v0)=(K; v). Defectless extensions have been extensively used to solve many problems in valuation theory. In this paper, we employ the notion of complete distinguished chains to give a di erent characterization of defectless extensions of a Henselian valued field.