Voice onset time

It is defined as the length of time that passes between the release of a stop consonant and the onset of voicing, the vibration of the vocal folds, or, according to other authors, periodicity.

The concept of voice onset time can be traced back as far as the 19th century, when Adjarian (1899: 119)[1] studied the Armenian stops, and characterized them by "the relation that exists between two moments: the one when the consonant bursts when the air is released out of the mouth, or explosion, and the one when the larynx starts vibrating".

However, the concept became widely known only in the 1960s, in a context described by Lin & Wang (2011: 514):[2] "At that time, there was an ongoing debate about which phonetic attribute would allow voiced and voiceless stops to be effectively distinguished.

The concept of VOT finally acquired its name in the famous study of Leigh Lisker and Arthur Abramson (Word, 1964), done while working together at Haskins Laboratories.

Because neither aspiration nor voicing is absolute, with intermediate degrees of both, the relative terms fortis and lenis are often used to describe a binary opposition between a series of consonants with higher (more positive) VOT, defined as fortis, and a second series with lower (more negative) VOT, defined as lenis.