Final answer:
A short musical idea is called a musical phrase. It is a short melodic or rhythmic idea that forms a complete musical thought.
Step-by-step explanation:
A short musical idea is called a(n) musical phrase. A musical phrase is a short melodic or rhythmic idea that forms a complete musical thought. It is like a musical sentence, with a clear beginning and end. For example, in the song 'Happy Birthday,' the phrase 'Happy birthday to you' is a musical phrase.
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