You know what a purr means and what a hiss signifies, but cats seem to
use meows as all-purpose communications. How can you interpret these
ubiquitous feline sounds? The key to translation lies in reading
Most often, a meowing cat just wants to be fed, especially if he or she is hanging out by the food bowl and it happens to be empty. Another common occasion for feline vocalization is the desire for attention. This is most likely the case if you've just arrived home or have been ignoring the cat for some time. Pick up the cat and pet it already!
However, meows can also be signs of more serious distress. A female in heat will meow continuously, and cats of either sex may meow constantly if they are in pain. Pay particular attention if your cat meows repeatedly while using the litter box; you may have to take your pet to the vet.
Cats meow for all sorts of reasons, so the best way to know what they're trying to say is to observe their behavior. A cat meowing near a copy of Heidegger's Being and Time may just be wondering: "Why are there beings at all instead of nothing? That is the question... when all weight tends to dwindle away from things and the sense of things grows dark, the question looms."
Source: Hill's Pet