Rattled

 is a Pokémon ability introduced in the fifth generation as a hidden ability. It increases speed when hit by certain types of attacks.

Description
When a Pokémon with this ability is hit by a Bug, Dark or Ghost attack, its Speed is increased by one stage. A multi-hit move like Pin Missile will trigger the ability with each hit.

As a Hidden Ability

 * Meowth (Alola Form)
 * Persian (Alola Form)
 * Magikarp
 * Ledyba
 * Sudowoodo
 * Dunsparce
 * Snubbull
 * Granbull
 * Poochyena
 * Whismur
 * Clamperl
 * Bonsly
 * Cubchoo

Trivia

 * The types that trigger Rattled are all super effective against Psychic-type Pokémon, though no Psychic-type Pokémon can have this ability.