We propose a novel method to expand a small existing translation dictionary to a large translation dictionary using a pivot language. Our method depends on the assumption that it is possible to find a pivot language for a given language pair on condition that there are both a large translation dictionary from the source language to the pivot language, and a large translation dictionary from the pivot language to the destination language. Experiments that expands the Indonesian-Japanese dictionary using the English language as a pivot language shows that the proposed method can improve performance of a real CLIR system.