Also called "vocal fry". A voice quality that is characterized by vocal cords that are more tense than during normal phonation, and a relatively low subglottal pressure. This causes the vocal cords to open and close more abruptly, creating broadband noise each time they open. This sound can best be described as creaking.
Creaky voice contrasts phonemically with modal voice in some languages, for instance Danish, in which the phenomenon known as "stød" appears to be realized as creaky voiced vowels. In other languages, such as English, creaky voice is used throughout parts of or entire utterances as a part of upper class speech.
Some people seem unable to use modal voice, and speak with creaky voice all the time. This can be very fatigueing to listen to, and it is not uncommonly regarded as a speech defect in need of treatment.