When cats are forced to watch prey just out of reach, they can’t contain their excitement and chattering could be an expression of this eagerness and anticipation.
That cute chattering sound could actually be little kitty curse words spewing out of your cat’s mouth as they express their frustration!
This mimicry tactic actually makes sense for ambush predators since as we say in the wild cat example, the goal is to lure the prey closer to you before pouncing.
Several likely factors contribute to the behavior, and rather than saying definitively what it is; it may be easier to say what it isn’t.
It’s hard to argue that it’s the primary reason behind cats’ chattering. Or really, even a secondary reason.
When cats chatter, it may sound slightly similar to a trill or chirp, but the movement of the mouth is entirely different.
If cat chattering occurs outside this context, like after a meal, it could be related to dental or oral pain and a cause for concern.