Noun
muroid (plural muroids)
Any rodent of the superfamily Muroidea; the hypernymy of the words in their strict/narrow senses is muroid (superfamily Muroidea) > murid (family Muridae) > murine (subfamily Murinae), although in broad use the taxon-specific distinctions below superfamily are often ignored.
The muroid family is broad and complex, and the common terms rat and mouse are not taxonomically specific. Source: Internet
Mouse often refers to any small muroid rodent, while rat refers to larger muroid rodents. Source: Internet