A yawn is a reflex in vertebrate animals characterized by a long inspiratory phase with gradual mouth gaping, followed by a brief climax (or acme) with muscle stretching, and a ra

Mar 15, 2024 · Yawning is a common reflex in which you open your jaw wide, take a deep breath, and then quickly breathe out. It lasts about 4-7 seconds and often happens when you're …

Oct 16, 2023 · When you yawn, several muscles in your face tense and stretch. Sometimes, this can pull on and stimulate your lacrimal glands, which leads to tears and watery eyes.

Aug 21, 2025 · Scientists still do not know exactly why we yawn, but they have several theories. Learn more about what causes yawning and why it is so contagious.

Oct 21, 2024 · A yawn is an involuntary reflex that involves opening the mouth wide and taking in a deep breath, followed by a slow exhale.

Aug 28, 2017 · Science explains the reasons why we yawn, whether animals yawn too, and how contagious yawning works. Also, sometimes it signals illness.

When we open our mouths to yawn, our jaws stretch down to their near-lowest position, heightening blood flow in the area that is then cooled by the quick intake of air.

The meaning of YAWN is to open wide : gape. How to use yawn in a sentence.

Oct 19, 2025 · Excessive yawning might be due to sleep disorders, medication side effects, or a health condition. Your provider may order an EEG, MRI, or overnight sleep test to determine …

We yawn when other people yawn, or itch when other people itch, because these are very old, herd-driven behaviors.