lengtecontrast

Lengtecontrast is a phonological phenomenon in which the length of a speech segment—most commonly a vowel, but sometimes a consonant—serves to distinguish meaning between words. When length is contrastive, two words can be distinguished solely by the duration of the segment, yielding a minimal pair.

There are two main forms of lengtecontrast. Vowel length contrast uses short and long vowels within the same phonological environment. Consonant length, also called consonant gemination, uses a short versus a geminated (long) consonant. Some languages exhibit only vowel length, others only consonant length, and some show both. The realization of length varies across languages and can interact with other features such as stress, syllable structure, and tone.

Phonologically, length can be described in terms of duration, mora count, or perceptual timing. In many languages, length is phonemic and affects lexical meaning, while in others it may reflect phonotactic patterns or allophonic rules rather than a lexical contrast. The perceptibility of length can be influenced by speech rate, vowel quality, and adjacent consonants.

Orthographically, length is often encoded in writing. Vowel length may be shown by diacritics or by doubling the vowel, whereas consonant length is typically indicated by double consonants in the orthography of many languages.

Lengtecontrast plays a central role in the phonology of many language families and interacts with morphology and phonotactics. See also phonology, vowel length, consonant length, and gemination.