A person raises both arms above the head and make a gesture of the letter "O". This gesture usually means ok, so the emoji is often used to express approval. It can also represent ballet because the gesture is similar to the movement of the upper body of a ballet dancer when dancing. There are two other versions of this emoji:
🙆♂ (man gesturing OK),
🙆♀ (woman gesturing OK). Related emojis:
👌🆗✔️❌⭕🚫🙅♂️🙅♀️🙋♂️🙋♀️