Definition - What does Linga mean?
Linga is a Sanskrit word meaning a "form" or "symbol." It is a main tantric symbol for Lord Shiva who is the destroyer and restorer, as well as the "god of yogis."
According to yogic texts, linga is the first and final form. It is believed that at the time of creation, the first form it took was that of an ellipsoid. Linga is a perfect ellipsoid and, as such, is considered the first form.
Yogapedia explains Linga
Linga has three parts. The uppermost part is called the Shiva pitha, the middle part is called the Vishnu pitha and the lower part is called the Brahma pitha, which lies underground.
Linga, also commonly referred to as Shiva lingam, denotes a phallus and the base of the linga is considered the yoni, or the female sex organ. The linga and yoni forms are suggestive of the creative energy of male and female.
Considered the cosmic symbol of unity, linga has been worshipped since ancient times. It is believed that worshipping linga on Maha Shivaratri produces amazing benefits to the body and soul.