Semivowel

A semivowel, also known as a glide, is a speech sound that is phonetically similar to a vowel sound but functions as the syllable boundary, rather than the nucleus of a syllable. It is articulated in a similar way to a vowel but does not form a syllable on its own. The terms "semivowel" and "glide" are often used interchangeably.

The defining characteristic of a semivowel is its non-syllabic nature. While vowels form the core of a syllable, semivowels function as consonants, often preceding or following vowels. They represent a rapid transition from one vowel-like articulation to another.

Common examples of semivowels include /j/ (as in "yes") and /w/ (as in "wet"). The sounds /j/ and /w/ are similar to the high vowels [i] and [u] respectively, but they are treated as consonants because they occur at the edges of syllables. In some languages, sounds like /r/ and /l/ can also function as semivowels in certain contexts, though this is less common.

The distinction between a vowel and a semivowel can sometimes be language-dependent and based on the phonological behavior of the sound within the language. A sound that functions as a vowel in one language might function as a semivowel in another.

In summary, a semivowel is a vowel-like sound that acts as a consonant, marking the boundary of a syllable rather than forming its core.