"Big Blue" is a phrase that has often been used to describe large blue objects or entities, such as the IBM corporation or the famous blue whale. However, there are several synonyms that can also be utilized to describe something of this nature. Examples include "majestic azure," "massive cobalt," and "gigantic sapphire." Other synonyms include "towering indigo," "enormous navy," and "grandiose cerulean." Overall, these words can be used interchangeably to describe anything that is large and blue, making them useful tools for any writer or speaker who is trying to diversify their vocabulary.