speech, freedom of, liberty to speak and otherwise express oneself and one's opinions. Like freedom of the press (see press, freedom of the), which pertains to the publication of speech, freedom of speech itself has been absolute in no time or place. The First Amendment to the U.S. Constitution bars the federal government from "abridging the freedom of speech"; since the 1920s the amendment's protections have been extended against state, as well as against federal, action.

Although speech is freer in the United States than in many societies, federal and state laws do restrict many kinds of expression. Some kinds of speech regarded as damaging to individual interests (e.g., libel and slander) are limited primarily by the threat of tort action; other forms of speech (e.g., obscenity) are restricted by law because they are regarded as damaging to society as a whole. Speech that is regarded as disruptive of public order has long been beyond protection (e.g., "fighting words" that cause a breach of the peace or false statements that cause general panic). The government also limits speech that threatens it directly; although sedition laws are rarely prosecuted in the United States, such rationales as a danger to "national security" have been invoked to silence criticism of or opposition to the government. Laws designed to silence opposition to organized religion (e.g., laws against blasphemy or heresy), common in some other countries, would run afoul of the First Amendment.

In recent decades speech controversies in the United States have involved, among other issues, whether and how "hate speech" directed at racial or other groups can be suppressed and what limitations may be imposed on speech in an attempt to combat sexual harassment. The definition of speech itself has been broadened to encompass "symbolic speech," which consists of actions that express opinions; thus, U.S. courts have held that burning the American flag as a protest is protected speech.

speech defect, any condition that interferes with the mental formation of words or their physical production. Speech defects in children generally become apparent in the early school years. Speech problems may arise from organic or functional abnormalities, but in practice the two are often hard to differentiate. Organic defects include deafness, cleft palate, dental abnormalities, and brain damage; most functional problems are basically psychological. Speech defects are generally categorized as disorders of sound production; disorders of voicing, e.g., loudness, pitch, and quality deviations; disorders of rhythm, such as stuttering and stammering; and disorders of language formulation and expression, including aphasia, the inability to use words as symbols of ideas. Treatment of a speech defect may include correction of organic conditions, psychotherapy, and training in proper articulation; it is rarely limited to a single type of therapy.

speech: see language.

part of speech, in traditional English grammar, any one of about eight major classes of words, based on the parts of speech of ancient Greek and Latin. The parts of speech are noun, verb, adjective, adverb, interjection, preposition, conjunction, and pronoun. Some grammarians add articles, quantifiers, and numerals. These word classes have traditional definitions in grammar books, i.e., "a noun is the name of a person, place, or thing" without reference to grammatical function. By this strict definition the word toy would be a noun in the sentence "The toy is under the tree" and in the sentence "It is a toy dog." However, an alternate method of defining parts of speech is in terms of the structural features and distribution patterns within a sentence. Thus toy would constitute a different part of speech in each of the above sentences since the word functions in different environments in each sentence, i.e., as a subject and as a modifier. Some English parts of speech (nouns, verbs, etc.) are productive classes allowing new members; others, with functional rather than lexical meaning (prepositions, articles, conjunctions) are nonproductive, having a limited number of members. See also inflection.

figure of speech, intentional departure from straight-forward, literal use of language for the purpose of clarity, emphasis, or freshness of expression. See separate articles on antithesis; apostrophe; conceit; hyperbole; irony; litotes; metaphor; metonymy; paradox; personification; simile; and synecdoche.

or voice recognition

Ability of computer systems to accept speech input and act on it or transcribe it into written language. Current research efforts are directed toward applications of automatic speech recognition (ASR), where the goal is to transform the content of speech into knowledge that forms the basis for linguistic or cognitive tasks, such as translation into another language. Practical applications include database-query systems, information retrieval systems, and speaker identification and verification systems, as in telebanking. Speech recognition has promising applications in robotics, particularly development of robots that can “hear.” Seealso pattern recognition.

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Human communication through audible language. Speech sounds are made with air exhaled from the lungs, which passes between the vocal cords in the larynx and out through the vocal tract (pharynx and oral and nasal cavities). This airstream is shaped into different sounds by the articulators, mainly the tongue, palate, and lips (see articulation). Articulatory phonetics describes each sound in terms of the position and action of the articulators used to make it. Speech is also described in terms of syntax, lexicon (inventory of words or morphemes), and phonology (sounds).

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Form of expression used to convey meaning or heighten effect, often by comparing or identifying one thing with another that has a meaning or connotation familiar to the reader or listener. An integral part of language, figures of speech are found in oral literatures as well as in polished poetry and prose and in everyday speech. Common figures of speech include simile, metaphor, personification, hyperbole, irony, alliteration, onomatopoeia, and puns.

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