Meaning of RAT in English
(n.) One of several species of small rodents of the genus Mus and allied genera, larger than mice, that infest houses, stores, and ships, especially the Norway, or brown, rat (M. decumanus), the black rat (M. rattus), and the roof rat (M. Alexandrinus). These were introduced into America from the Old World.
Webster's English dictionary. Английский словарь Webster. 2012