Speech disfluencies are parts of speech which are not generally recognized as purposeful or containing formal meaning, usually expressed as pauses such as uh or er, but also extending to repairs ("He was wearing bla—uh, blue pants"), and articulation problems such as stuttering. Use is normally looked down upon in mass media such as news reports or films, but they occur regularly in everyday conversation.

Americans use pauses such as "um" or "uh," the British say "er," the French use something like "euh," and Hebrew and Spanish speakers use something like "ehhh." Other languages have their own syllables for these pauses.

Recent linguistic research has suggested that non-pathological disfluencies may contain a variety of meaning; the frequency of "uh" and "um" in English is often reflective of a speaker's alertness or emotional state. Some have hypothesized that the time of an "uh" or "um" is used for the planning of future words; other researchers have suggested that they are actually to be understood as full-fledged words rather than accidents, indicating a delay yet to come. There is some debate as to whether to consider them a form of white noise or as a meaning-filled part of language.

Speech disfluencies have also become important in recent years with the advent of text-to-speech programs and other attempts at enabling computers to make sense of human speech.

In America, since the 1980s, the word "like" has been used in the same way as "um" or "uh" as filler words, and is widespread among youth. For example, "I, like, don't know" instead of "I, uh, don't know" (see Like#Valley speak and beatniks for more information). Some people increasingly use both "like" and "um" to the point where they put them together, for example, "like, um... I don't know."

References

• Michael Erard, "Just Like, Er, Words, Not, Um, Throwaways," New York Times, January 3, 2004.