My cat knows exactly what it wants when it yells at me. I just had to learn how to speak cat.
The meowing is just to get my attention. Once walk over to him, he'll walk over to the place he wants me to go. At that point I have to figure out what he wants me to do there, but it's usually food dish/water dish/couch for lap sitting.
This is exactly why I usually say it means "Something's wrong" instead of "I want something" because the cat is perfectly capable of occupying un-pillowed laps, it just chooses not to.
I suppose in that respect, it does mean "I yearn!" but I've taken it to mean "Something's wrong!", with the nuance being that he'll want his food bowl filled even if he's not hungry or me on the couch even if he doesn't immediately want a lap.
Do you blame them? Half of ‘em don’t even get to go outside at all much less when they want to. How would you feel if you were on house arrest for your whole life?