The term "Rudraksha" is derived from two Sanskrit words: "Rudra" (another name for Lord Shiva) and "Aksha" (meaning eyes). According to Hindu mythology, Rudraksha beads were formed from the tears of Lord Shiva. These beads come in different "mukhis" or faces, each representing different energies and deities.

The 1 Mukhi Rudraksha, also called the Ek Mukhi Rudraksha or One Faced Rudraksha, is the rarest and most powerful form among all Rudrakshas. It has only one natural groove or face on its surface and is believed to be the purest embodiment of Lord Shiva himself.

https://www.divinehindu.in/pro....ducts/1-mukhi-rudrak