It is called atari 当たり.
The word is connected to the verb ataru 当たる.
Which indeed can mean to hit, to meet, to collide, to touch, to clash.
Compare atemi 当て身.
You move the partner using "the point at which the ki collides". (see 0:40)
He may have said that but it is not what I saw. I saw no clashing only blending and redirection.