A plague is a very infectious disease that spreads quickly and kills large numbers of people.

Plague or the plague is a very infectious disease which usually results in death. The patient has a severe fever and swellings on his or her body.

A plague of unpleasant things is a large number of them that arrive or happen at the same time.

If you describe something as a plague, you mean that it causes a great deal of trouble or harm.

If you are plagued by unpleasant things, they continually cause you a lot of trouble or suffering.

If someone plagues you, they keep bothering you or asking you for something.

If you say that you avoid someone or something like the plague, you are emphasizing that you deliberately avoid them completely.

You say a plague on a particular person or thing when you are very irritated by them and do not want to bother with them any more.