The constellation represented by a lion is Leo. Its name is Latin for “lion,” and Greek mythology associated it with the Nemean Lion, the fearsome creature defeated by Heracles during his first labor. The lion’s hide was said to be impervious to ordinary weapons, so Heracles killed it through sheer strength and later wore its skin as armor.
Leo is one of the 12 zodiac constellations and one of the 48 listed by the second-century astronomer Ptolemy. It remains one of the 88 constellations officially recognized today. Its stars form a pattern that many observers describe as a crouching lion, although constellation outlines are cultural interpretations rather than physical groupings of nearby stars.
A common mix-up is Leo Minor, whose name means “little lion.” Leo Minor is a separate, much fainter constellation located near Leo. Leo is also notable for the Sickle asterism, a backward-question-mark shape formed by several bright stars, including Regulus, the constellation’s brightest star.