Muses (sacred poetry) is often seen with a pensive expression; Terpsichore (choral dance and song) is often seen dancing and carrying a lyre; Thalia (comedy) is often seen with a comic mask; and Urania (astronomy) carries a pair of compasses and the celestial globe. Greek "mousa" is a common noun as well as a type of goddess: it literally means "art" or "poetry". According to Pindar, to "carry a "mousa"" is "to excel in the arts". The word derives from the Indo-European root "men-", which is also the source of Greek "Mnemosyne" and "mania", English "mind", "mental" and "monitor", Sanskrit "mantra"
Greek chorus the sense 'I am dancing'. The word "ode" means not something recited or declaimed, but 'a song'. The 'orchestra', in which a chorus had its being, is literally a 'dancing floor'." From this, it can be inferred that the chorus danced and sang poetry. Plays of the ancient Greek theatre always included a chorus that offered a variety of background and summary information to help the audience follow the performance. They commented on themes, and, as August Wilhelm Schlegel proposed in the early 19th century to subsequent controversy, demonstrated how the audience might react to the drama. According to Schlegel,