A cats may meow more than usual when it is hungry, wants attention or is not feeling well, says WebMD. Older cats with certain mental conditions may meow more when they get confused or lost.
Adult cats reserve their meows for their human companions, notes the American Society for the Prevention of Cruelty to Animals. Cats yowl, hiss and growl at other cats, but do not meow at them. Some breeds of cats, such as the Siamese and oriental shorthair, are naturally more vocal than other breeds. If a cat suddenly starts meowing more than usual, it's a good idea to schedule an appointment with a veterinarian.