(USED WITHOUT OBJECT)
to open the mouth somewhat involuntarily with a prolonged, deep inhalation and sighing or heavy exhalation, as from drowsiness or boredom.
to open wide like a mouth.
to extend or stretch wide, as an open and deep space.
(USED WITH OBJECT)
Archaic. to open wide, or lay open, as if by yawning.
A yawn is a reflex consisting of the simultaneous inhalation of air and the
stretching of the eardrums, followed by an exhalation of breath. Yawning (
Sep 23, 2011 ... People yawn more easily in cooler temperatures, supporting the idea that
yawning cools the brain.
Aug 19, 2014 ... Scientists working to unravel the mystery surrounding the yawn, and why it's
contagious, have discovered that yawning is much more ...
Next time you're in a meeting, try this little experiment: Take a big yawn, cover
your mouth out of courtesy and watch to see how many people follow suit.
May 12, 2014 ... A new study has suggested that the reason we yawn has nothing to do with
tiredness or boredom, but actually works in order to cool down our ...
The study of yawning is anything but boring. It boasts a rich history of theories
that go back to Antiquity, but thus far the biological function of yawning remains a
Apr 14, 2014 ... Yawning may be the opposite of what we think—not a signal of sleepiness but a
signal that it's time to act.
Aug 12, 2014 ... Yawning has puzzled scientists for more than two millennia. But could a new
theory settle the question once and for all? David Robson ...