Pronunciation: [nˈɔːwe͡ɪ ɹˈat] (IPA) 
The Norway Rat, also known as Rattus norvegicus, is a common pest found all over the world. The spelling of "Norway" in this context is pronounced /ˈnɔːrweɪ/ in the International Phonetic Alphabet. It is derived from the country of Norway, as the rats were believed to have originated from there. The word "rat" is spelled /ræt/ in IPA and is a Middle English term that has been used since the 14th century.
The Norway rat, scientifically known as Rattus norvegicus, is a large, resilient, and omnivorous rodent species belonging to the family Muridae. Also referred to as the brown rat, sewer rat, or common rat, it is one of the most widespread and successful mammals worldwide. The Norway rat is characterized by its robust build, short ears, and a tail that is shorter than its body.
Measuring approximately 9-11 inches in length, excluding the tail, and weighing between 7-18 ounces, the Norway rat possesses a distinctive fur coat that is typically brown or gray-brown, interspersed with scattered black hairs. Its tail is scaly and nearly hairless. This rat species has a high reproductive rate, with females producing multiple litters in a year and giving birth to up to twelve young in each litter.
The Norway rat is an adaptable and highly opportunistic animal that lives in a variety of environments, including urban areas, fields, forests, and even near bodies of water. It constructs elaborate burrows, often found near buildings or in sewers, where it nests, stores food, and seeks refuge. As an omnivorous species, it feeds on a wide range of items, including grains, fruits, vegetables, meat, and garbage.
Norway rats are known to be vectors of various diseases and may damage property, structures, and crops. Due to their impacts on human health and agriculture, efforts to control their populations have been made through various methods, including trapping, poisoning, and rodent-proofing.
The etymology of the term "Norway rat" can be traced back to the rat species' origins and its association with Norway. However, it is important to note that despite its name, the Norway rat (Rattus norvegicus) did not originate in Norway.
The origin can be traced to the Old World, specifically Asia. It is believed that the species originated in China or Mongolia. From there, it spread through Europe during medieval times, possibly through trade routes and ships.
The term "Norway rat" emerged as a result of a misconception in the 18th century when the species was first scientifically described. The rat was mistakenly believed to have come to England from Norway by ships, leading to it being erroneously named the "Norway rat". The name stuck, even though Norway had no association with the species other than this misperception.
