Merriam-Webster's Collegiate® Dictionary, 11th Edition
MOUSE
I. noun (plural mice)
Etymology: Middle English, from Old English mūs; akin to Old High German mūs mouse, Latin mus, Greek mys mouse, muscle Date: before 12th century any of numerous small rodents (as of the genus Mus ) with pointed snout, rather small ears, elongated body, and slender tail, a timid person, a dark-colored swelling caused by a blow, a small mobile manual device that controls movement of the cursor and selection of functions on a computer display,
II. verb (moused; mousing)
Date: 13th century
intransitive verb to hunt for mice, to search or move stealthily or slowly, transitive verb
1. obsolete bite , gnaw , to toy with roughly, to search for carefully