PERCUSSION - A Western category of musical instruments creating sound by "striking" or "shaking" and divided further into those that produce a definite pitch (e.g., timpani) and those that produce an indefinite pitch (e.g., snare drum).

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percussion are contained in chamber orchestra
percussion has example timpani
percussion has example snare drum
percussion has example Bass Drum
percussion has example Glockenspiel
percussion has example Cymbals
percussion has example Xylophone
percussion instruments (categories) of symphony orchestra
percussion is/are Western category of instruments