Fast Talking, Fast Speaker, Fast Speaking, Quick Talker
Noun and の adjective
はやくち
はやぐち
わたしの兄は、とても早口です。
My older brother is a really fast talker.
お前のことが一ばん大すきだよって、何でそんなに早口で言ったの？
Why did you say that you love me the most so quickly?
こんなに早口の赤ん坊なんて見たことないよ。
I’ve never seen such a fast talking baby before.
When you have a fast mouth, you're probably a fast talker, right motormouth?
Remember how body parts often change even jukugo words to kun'yomi readings? That's what happened here too. Both readings are kun'yomi, making this one はやくち. Alternatively, you can read this as はやぐち as well.