In this paper, the author introduces and explores the concept of synesthetic language, a multisensory linguistic system that integrates various sensory experiences into fundamental units called “synesthemes.” The author argues that synesthetic language forms the foundation of our internal thought processes, while communication with others involves translating between this internal language and externally-oriented languages, such as English, Chinese, Spanish, and other conventional languages. Drawing on evidence from cognitive science, linguistics, and psychology, the paper demonstrates that although one sense often dominates external communication languages, elements of other senses are present in the form of tone, body language, and nonverbal cues. The author further addresses counterarguments to the Sapir-Whorf Hypothesis, reconciling the relationship between bilingual cognition and internal synesthetic language. This exploration of synesthetic language contributes valuable insights into the complex interplay between sensory experiences, human thought, and communication, with potential implications for a deeper understanding of linguistic and cognitive processes.