Animal Talk is a term used to describe the various forms of communication used by animals. YAK is a three-letter word that refers to a long-haired wild ox found in the Himalayas. DELTA is a five-letter word that refers to the fourth letter of the Greek alphabet, which is often used to represent change or difference. Together, these two words can be used to describe the various forms of communication used by animals, such as yaks communicating with each other through sound and DELTA waves being used by dolphins to communicate with each other.