reed pipe; grass whistle
A simple musical instrument made by blowing across a blade of grass or a leaf held between the thumbs or lips. Often associated with children's play and folk culture.
When I was a child, I often played by blowing a grass whistle.
He made a reed pipe out of a bamboo leaf.
Standard kanji spelling; the word is commonly written in kanji.
Compound of 草 (kusa, 'grass') and 笛 (fue, 'flute, whistle'). The exact historical origin is uncertain, but the word straightforwardly describes a whistle made from grass or leaves.