From Bulbapedia, the community-driven Pokémon encyclopedia.
A status move is a move that, in the Pokémon games, does no direct damage, but instead causes a weather condition, status ailment, or changes the stats of a Pokémon during battle. This includes also other attacks which cannot be categorized under physical moves and special moves because of their unique or nearly-unique effects, such as Destiny Bond, Splash, Charge, and Recover. Status moves fall under the Other category in Pokémon Mystery Dungeon: Explorers of Time, Darkness and Sky.
The majority of Normal- and Psychic-type moves, as well as the only ???-type* move, Curse, are in this category. Very few moves of the other 15 types are status moves; for example, the Dragon type only features one status move, while Fire only features two.