Word
The technical term word represents a 16-bit byte, or two 8-bit bytes with 65536 distinct identifiers. In all main-series Pokémon games after Generation II Pokémon species identifiers are stored in words, hence there are 65151, 65044 and 64877 invalid identifiers representing 'glitch Pokémon in Generation III, Generation IV and Generation V main series Pokémon games respectively.