This is a video in which the cat appears to say “No, No!” repeatedly. It is a funny cat video…
However, the cat is simply vocalising a sound when in an anxious and submissive state when expecting to be attacked by the look of the cat’s flattened ears which are in the defensive, protected position. Cats protect their ears which are easily damaged in a fight.
The sounds and/or behavior that domestic cats make under these circumstances varies a lot but sometimes, rarely, the sound, by pure chance, mimics the sound of the word “No”. The sound made by another cat may be similar to another short word. It is just pot luck.
The question I have, which is not funny unfortunately, is why is this cat fearful? Is there someone out of view who is doing something that makes the cat nervous? It looks that way to me.
My thanks to Dee for finding the video. Associated: Cat Sounds.