The story
Likely from Wotter (“nickname for Oshawott”) + -gate, influenced by Watergate.
Etymology from Wiktionary, CC BY-SA 4.0.
Wottergate
Today it means: The controversy surrounding the leaked final evolutions of the Unova starter Pokémon prior to the release of Pokémon Black and White, which sparked widespread fan backlash and disbelief that the designs were genuine. Full definition →