the.com/brown rat

means A large burrowing rat (Rattus norvegicus) with coarse brown fur, native to Asia, now the dominant rat species worldwide and the ancestor of pet and lab rats.

from Its scientific name norvegicus means 'of Norway' — a 18th-century naming mistake. The species actually originated in northern China and Mongolia and spread west along trade routes and ships, but an early naturalist wrongly assumed it had arrived in Britain aboard Norwegian timber ships, and the misleading label stuck even after the error was known. 'Rat' itself is an old Germanic word, possibly related to Latin 'rodere' — to gnaw — though that link is more suggestive than certain.