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Dawid Trzensimiech, Royal Ballet Artist, and Akane Takada, Royal Ballet First Artist, demonstrate pirouettes.
Pirouette: A famous ballet movement in which the dancer performs a complete turn en pointe or demi-pointe. Pirouettes may be performed in any given position, in arabesque, in second position, etc.
Origin:
From Old French pirouet, spinning top.
Read more: http://www.roh.org.uk/discover/ballet/glossary.aspx