I have finished virtually all of my homework.In Modern American Usage, Bryan A. Garner counts virtually as a weasel-word. Weasel-words are so named because of the habit of weasels to attack birds' nests, and eat their eggs by sucking the meat out, leaving an empty shell." Likewise, words such as virtually "have the effect of rendering uncertain or hollow the statements in which they appear."
This new surgical procedure is virtually pain-free.
So be careful using virtually, or other words that similarly diminish the words around them. Other weasel-words commonly used by writers today include significantly, obviously, very, and quite.