Source : Webster's Revised Unabridged Dictionary (1913)

Mousy \Mous"y\, a.
   Infested with mice; smelling of mice.

Source : WordNet®

mousy
     adj 1: timid and ineffectual [syn: {mousey}]
     2: having a drab pale brown color resembling a mouse; "a mousy
        grownish-gray color"; "mouse-colored hair"; "a mouselike
        rodent" [syn: {mouse-colored}, {mouselike}]
     [also: {mousiest}, {mousier}]