To reduce or fail in value, often referring to currency.

To make something seem less impressive or important.

कम अहमियत देना

English Usage: His criticisms seem to devaluate all the hard work we put into the project.

Hindi Usage: उसकी आलोचनाएँ हमारे प्रोजेक्ट में किए गए कठिन परिश्रम को कम अहमियत देती हैं।