The term PET STORE SOUND is composed of two crossword solutions, CHEEP and 5 letters. CHEEP is a sound that is commonly associated with pet stores, as it is the sound made by birds, which are often sold in pet stores. The 5 letters refer to the other animals that are typically found in pet stores, such as cats, dogs, fish, and reptiles. Together, these two solutions represent the sounds that can be heard in a pet store.