Tonal language

A tonal language is one in which changes in pitch lead to changes in word meaning. Perhaps the best-known examples are Mandarin Chinese and Cantonese, but in fact, many unrelated languages are tonal. Some language groups that contain tonal languages include Sino-Tibetan (to which the Chinese languages belong), Austro-Asiatic (which include Thai and Vietnamese), the Bantu languages (almost all languages in Sub-Saharan Africa are Bantu).

To illustrate how tone can affect meaning, let us look at the following example from Mandarin Chinese, which has five tones:

1 is a long, high level tone

2 starts at normal pitch and rises to the pitch of tone 1

3 is a low tone, dipping down briefly before slowly rising to the starting level of tone 2

4 is a sharply falling tone, starting at the height of tone 1 and falling to somewhere below tone 2's onset.

. (dot) or 0 is a neutral tone, with no specific contour; the actual pitch expressed is directly influenced by the tones of the preceding and following syllables

These tones can lead to one syllable, "ma" having five meanings, depending on the tone associated with it, so that "ma1 ma0" glosses as "mother", "ma2" as "hemp", "ma3" as "horse", "ma4" as "scold", and "ma0" at the end of a sentence acts as an interrogative particle. This differentiation in tone allows a speaker to create the (not entirely grammatical) sentence "ma1 ma0 ma4 ma3 de0 ma2 ma0?", or "Is Mother scolding the horse's hemp?", where the series of "ma"s are differentiated in meaning only by their tone.

Tones can interact in complex ways through a process known as tone sandhi.

Tonal languages fall into two broad categories: register and contour systems. Mandarin Chinese and its close relatives have contour systems, where differences are made not based on absolute pitch, but on shifts in relative pitch in a word. Register systems are found in Bantu languages, which more typically seem to have 2 or 3 tones with specific relative pitches assigned to them, with a high tone and a low tone being the most common (plus a middle tone for languages that have a third pitch).

Please note that the word "pitch" is used loosely here, to refer to the comparative difference between a high pitch and a low pitch from one syllable to the next, rather than a contrast of absolute pitches such as one finds in music. As a result, when one combines tone with sentence contours, the musical pitch of a high tone at the beginning of a question may actually be lower than the musical pitch of a low-tone word at the end of the question, because the "average" pitch between the high and low tones rises (and falls) along with the overall pitch contour of the sentence.