What was the original full Japanese title behind the international name Pokémon?

The original full title behind the international name Pokémon was Pocket Monsters.

In Japan, the franchise was launched as Pocket Monsters, commonly written in Japanese as Poketto Monsutā. Pokémon is the shortened international form of that name, with an acute accent added to the e to guide pronunciation in many markets.

The name refers both to the fictional creatures and to the wider franchise, which includes video games, animation, films, manga, merchandise, and the Trading Card Game. In English, Pokémon is normally used for both singular and plural forms.

The international abbreviation helped the brand travel across languages and media while preserving its Japanese identity. The original game releases were titled Pocket Monsters Red and Green in Japan, whereas international releases used Pokémon Red and Blue.