Glottal stop

A glottal stop or glottal plosive is a type of consonantal sound used in many spokenlanguages, produced by obstructing airflow in the vocal tract or, more precisely, the glottis. It is familiar to English speakers as the catch in the middle of "uh-oh". The symbol in the International Phonetic Alphabet that represents this sound is ⟨ʔ⟩.

As a result of the action of the glottis, glottal vibration either stops or becomes irregular with a low rate and sudden drop in intensity.