(eks-ten'sÅr, -sÅr), [TA] 1  A muscle the contraction of which causes movement at a joint with the consequence that the limb or body assumes a more straight line, or so that the distance between the parts proximal and distal to the joint is increased or extended; the antagonist of a flexor. See: muscle.
All other things being equal, using internal rate of return (IRR) and net present value (NPV) measurements to evaluate projects often results in the same findings. However, there are a number of projects for which using IRR is not as effective as using NPV to discount cash flows.
Notice that when the discount rate is lower than the internal rate of return, our NPV is positive (as shown in the first example above). Conversely, when the discount rate is higher than the IRR, the resulting net present value is negative (as shown in the second example above).