Nyarth

Meowth is a small, feline Pokémon with cream-colored fur that turns brown at the tips of its hind paws and tail. Its ovoid head features four prominent whiskers, wide eyes with slit pupils, two pointed teeth in the upper jaw, and a gold koban coin embedded in its forehead. Its ears are black with brown interiors and are flanked with an additional pair of long whiskers. Meowth can freely manipulate its claws, retracting them when it wants to move silently. The tip of its tail curls tightly. Meowth is a quadruped with the ability to walk on its hind legs. While the games almost always depict Meowth on two legs, it is stated in the Pokémon the Series episode Go West Young Meowth (EP072) that Meowth normally walks on all fours.

Meowth is attracted to round and shiny objects and has the unique ability to produce coins using its signature move, Pay Day. Being nocturnal, it is known to wander about city streets at night and pick up anything that sparkles, including loose change. Upon finding a sparkling object, its eyes will glitter and the coin on its forehead will shine brightly. It shares this intrigue with Murkrow, with whom it often fights with for objects and prey. Meowth is a playful but fickle Pokémon with the capacity for human-like intelligence, with at least one member of the species teaching itself how to speak. Meowth tends to live in urban areas. As mentioned in Pokémon Sleep, Meowth is known to sleep with the coins it collects.

Forms
Meowth has a Gigantamax form and two regional forms, Alolan Meowth and Galarian Meowth.

Alolan Meowth
In Alola, Meowth has a slightly different look. This look was the result of the monarchy's influence. Alolan Meowth's fur is a light blue-gray color. Instead of brown markings, the tip of its tail, whiskers, digits, and the insides of its ears a whitish-gray. Alolan Meowth's whiskers have a slight curve compared to regular Meowth's straighter whiskers, and it has silvery eyes.

Meowth was introduced to Alola as a gift to royalty. The luxurious royal lifestyle soon led to Meowth diverging from its origins and becoming the selfish, prideful, and cunning Alolan Meowth. As a result, Alolan Mewoth's new pride also made them impulsive and fickle in nature. Alolan Meowth will turn hysterical if its coin or pride are besmirched. Due to the actions of humans in Alola, Alolan Meowth's population increased in numbers. When the monarchy fell, the rare Alolan Meowth went feral and eventually grew as common in Alola as anywhere else. Alolan Meowth is known to be very famously difficult to train due to their arrogant nature. Despite this, Alolan Meowth is also very popular with some Trainers who enjoy giving it a lot of attention.

Galarian Meowth
Galarian Meowth has a shaggy, greyish-brown coat resembling a beard, as well as yellow eyes and a toothy grin. Its coin is now black and extremely hard, with the darkest and hardest coins being especially valued and respected among the species.

Galarian Meowth's body has partially turned to iron as a result of many years of living with a race of savage seafarers. As a result of many battles, Galarian Meowth develops the ability to evolve into Perrserker, instead of Persian. Kantonian Meowth and Galarian Meowth don't get along.

Gigantamax Meowth
Some Kantonian Meowth are capable of Gigantamaxing. As Gigantamax Meowth, it has become larger and longer in size. The body extends from the lower half to the shoulder, while the gold coin gains a symbol. Meowth's eyes change to a glowing gold color. The tail grows long as well, with the end of its tip extending. The tail gets even larger and bumpy when it uses an attack. Three red clouds surround it below the shoulders.

The giant coin on Gigantamax Meowth's head emits a lot of Gigantamax power that surrounds the area with a golden gleam. Its desire for shiny objects increases to the point where it will cause damage to skyscraper windows and exterior walls for the sake of sharpening its claws. The symbol on Gigantamax Meowth's gold coin is believed to be the key to unlocking the secrets of Dynamax.

Evolution
Meowth evolves into Persian.
Alolan Meowth evolves into Alolan Persian.
Galarian Meowth evolves into Perrserker.

(Source: Bulbapedia)