If a dog sweats through his tongue what are his armpits for?
Their main way to cool down is through panting or breathing very rapidly which cool them internally. They do not have armpits, because they do not have arms. Those aren't pits; they're called flanks. They have 4 legs.
Dogs do have "sweat glands" on their paws. They do sweat heavily through their feet. That's why it is recommended that if you have a long-haired dog or a dog that requires frequent grooming to make sure you take it to a groomer on schedule to have its feet cleaned up.
When a dog is hanging out its tongue because it is hot, its tongue gets larger and the dog will pant. These quick breaths will cause the tongue to evaporate moisture which in turn cools the dog's tongue. As blood flows through the tongue, the blood is cooled off. It is then transported back to the body, which helps lower the dog's body temperature.
Usually it means that they're trying to cool down. When a dog pants, moisture from the dog's exhaled breath condenses on the tongue and then evaporates into the air. This evaporation causes the surface of the tongue to cool. As the tongue cools, the blood flowing through it also cools and helps cool the dog's entire body through the circulatory system.