Definition of mousing:
(n) :
(computing) Use of the mouse
(n) :
The act of hunting mice (or similar prey), especially by pouncing on them from above.
(n) :
(nautical) A turn or lashing of spun yarn or small stuff, or a metallic clasp or fastening, uniting the point and shank of a hook to prevent its unhooking or straightening out.
(n) :
A ratchet movement in a loom.
(adj) :
Impertinently inquisitive; prying; meddlesome.