open (adj.)

A term used in the four-level phonetic classification of vertical tongue movement in vowel sounds based on the cardinal vowel system, the others being close, ‘half-close’ and ‘half-open’. It refers to a vowel made with the tongue in the lowest possible position, i.e. the mouth as wide open as possible, as in [a] and [a]: the most open vowels in English are in words like cat and cart. The area of articulation immediately above ‘open’ is known as half-open or mid-open, as in [ε] and  (the nearest English vowels being in words like get and got respectively). In a three-level classification of vowel sounds, the lowest group are known as ‘low’ vowels (as opposed to ‘high’ and ‘mid’).

Open is used in the classification of lip positions, referring to the visual appearance of the lips when they are held relatively wide apart, but without any noticeable ROUNDING, as in such sounds as the [a] in part. It is contrasted with SPREAD, NEUTRAL and rounded positions. A similar notion is involved in the classification of JAW SETTINGS.

A term used in the two-way classification of SYLLABLE structure, referring to a syllable which ends in a VOWEL, as opposed to the CLOSED syllable, which ends in a CONSONANT. This feature is sometimes referred to as a ‘free’ syllable. The open syllable is the first syllable type to be productively used by children, in the early stages of PHONOLOGICAL development. It also constitutes a syllable type (consonant+ vowel) which seems to be a UNIVERSAL feature of LANGUAGE.

A term sometimes used in the GRAMMATICAL CLASSIFICATION of WORDS to refer to one of two postulated major word-classes in language, the other being CLOSED. An open class is one whose membership is in principle indefinite or unlimited. New items are continually being added, as new ideas, inventions, etc., emerge. NOUNS, VERBS, ADJECTIVES and ADVERBS are open-class items, whereas CONJUNCTIONS, PRONOUNS, etc., are closed. The distinction is not quite as clear-cut as it seems, as the class of PREPOSITIONS in English, for example, is relatively open (e.g. in accordance with, on account of, and many more), and within the so-called open classes of words there are several closed subsystems, e.g. AUXILIARY verbs. But the contrast between ‘open’ and ‘closed’ is widely recognized.

In early language ACQUISITION studies of the two-word stage of grammatical development, the term refers to the variable ELEMENT in a CONSTRUCTION, the other being referred to as the PIVOT. For example, in the set daddy there, cat there, drink there, there is the pivot word (a member of a small, ‘closed’ class), and daddy, etc., are members of an open class. The distinction is of largely historical interest today.

A term used in the classification of types of JUNCTURE or TRANSITION, referring to the features which help to define a word boundary, before silence; also known as ‘plus juncture’. Open juncture is opposed to close juncture; ‘open transition’ to ‘close transition’.