Tangrowth is the Pokémon who serves as Professor Tangrowth in Pokémon Pokopia.
After Ditto awakens in the abandoned world, it meets a Tangrowth who has taken on the role of a researcher. Professor Tangrowth studies the damaged environment and investigates the mystery of why humans and Pokémon disappeared from the region.
The name is a title-based character name rather than a separate Pokémon species. Tangrowth is the species, while “Professor Tangrowth” identifies this particular story character and their scientific role. That distinction can cause confusion with other professor characters from the Pokémon series, such as Professor Oak or Professor Rowan.
Professor Tangrowth becomes Ditto's early partner in restoring habitats. Together, they examine the world, help Pokémon recover, and uncover clues about the past. The character therefore functions as both a story guide and an in-world researcher.