I've personally never seen a dire wolf called a monster. Not saying it doesn't happen.

My first reaction to seeing a question like this is to simply look at a dictionary. According to dictionary.com...


1.
a legendary animal combining features of animal and human form or having the forms of various animals in combination, as a centaur, griffin, or sphinx.
2.
any creature so ugly or monstrous as to frighten people.
3.
any animal or human grotesquely deviating from the normal shape, behavior, or character.
4.
a person who excites horror by wickedness, cruelty, etc.
5.
any animal or thing huge in size.
6.
Biology.
an animal or plant of abnormal form or structure, as from marked malformation or the absence of certain parts or organs.
a grossly anomalous fetus or infant, especially one that is not viable.
7.
anything unnatural or monstrous.

As you can see, most if not all of Antarctic Termite's points were true. The word has been around for a long time, and has gained a lot of different meanings. The one over branching detail is that monsters have the power to scare most humans.