Certain canines are a type of dog that have been bred for specific characteristics, such as size, coat color, and temperament. They are often used as working dogs, guard dogs, or pets. The term 'certain canines' can refer to any breed of dog, but the most common breeds include German Shepherds, Labrador Retrievers, and Golden Retrievers. The crossword solution for the term 'certain canines' is TEETH, which refers to the fact that all dogs have TEETH, regardless of breed.