Libra/ˈliːbrə/ Definition 1 of 4Pro Tip 1/2Zodiac Constellation Libra refers to a specific formation of stars often studied in astronomy. The textbook had a chapter dedicated to the Libra constellation. Pro Tip 2/2Not Always Visible Libra might not be visible all year round depending on your location and the season. I could observe Libra in the sky during the autumn months.