Decuple is defined as multiplying something by ten or an increase of ten times. Some synonyms for the word decuple include tenfold, decennial, decade-long, ten times, decuple, tenfold increase, ten-fold growth, and decuplication. These words give a sense of size and scale. For example, we can use tenfold increase to describe an upward trend, or decuple to describe the massive growth of a company. Decennial could be used to describe the passage of ten years, or a decade-long partnership between two businesses. Understanding synonyms for decuple allows for deeper language and communication of growth, expansion, and change.