Sméagol’s later name in J.R.R. Tolkien’s The Lord of the Rings was Gollum.
Sméagol was a Hobbit-like Stoor who lived near the Gladden Fields. On his birthday, he went fishing with his relative Déagol, who discovered the One Ring. Sméagol murdered Déagol to take the Ring and was eventually driven away by his people because of his secrecy and corrupt behavior.
The Ring prolonged Sméagol’s life while twisting his body and personality. He hid beneath the Misty Mountains for centuries, where he became known as Gollum, a name associated with the choking or swallowing sound he made in his throat. Tolkien presents Sméagol and Gollum as conflicting aspects of one character rather than two separate beings.
Déagol is the relative who finds the Ring, not the later name of its murderer. Gríma is Wormtongue, and Shelob is a giant spider, so neither belongs to Gollum’s identity or origin story.