The Definition for these Musical Terms please ?

Hi, I have my GCSE exam on friday and I would i would really appreciate your help in understanding these African Music Terms,
Djembe
Donno
Dun-Dun
Mbira
Kora
Balophone
Master Drummer
Call and Response
Improvisation
Polyphony
Counterpoint
Cross Rhythms
Tone Languages
Pentatonic Scale

Djembe is a type of drum used in West Africa.

Donno is one of many names given to the talking drum.

Dundun is a bass drum used in West Africa.

Mbira is an African thumb piano, it’s a lamellophone.

Kora is a harp-lute used by West African griots.

Balafon is a tuned idiophone related to xylophone.

I think it’s obvious who a Master Drummer is!

Call and Response is a musical form where one musician kind of answers the phrases of the other.

Improvisation – PLEASE!!! You can’t be serious you don’t know the meaning of that.

Polyphony is a musical texture where at least two independent voices are active simultaneously and the relationship between them is called counterpoint.

Cross-rhythm is a type of polyrhythm. From New Hardward Dictionary of Music: A rhythm in which the regular pattern of accents of the prevailing meter is contradicted by a conflicting pattern and not merely a momentary displacement that leaves the prevailing meter fundamentally unchallenged.

Pentatonic scale is any scale consisting of five pitches.

Tonal languages, well this is a linguistic term. In linguistics, the term ‘tone’ differs greatly from its musical definition (a perceivable fundamental frequency with a predefined relative length of duration). The linguistic meaning is the use of pitches or portamenti (glides from one pitch to another) to distinguish lexical or grammatical meaning. Chinese is the best known tonal language and it distinguishes between four tones – rising, falling, falling-rising (the use of portamenti) and static (the use of pitch). A word may thus have different meanings depending on the tone whereas in English, the tone doesn’t affect the meaning of a word. Most of Sub-Saharan languages are tonal.

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