Often the word 'ironic' is much misused to remark on a coincidence, such
as, “This is the third time today we have run into each other. How
ironic.” It is also mistakenly used to describe something out of the
ordinary or unusual, “Yesterday was a beautiful, warm day in November.
Truly ironic.” It is also wrongly used to emphasize something
interesting. For example, “Ironically, it was the best movie I have seen
all year.”
A true ironic remark conveys a meaning that is the opposite of its
literal meaning, so in an ironic statement one thing is said, while
another thing is meant. For example, it would be irony on a nasty
stormy to say, “What wonderful weather.” If you were suffering from a
bad cold you might say, “I feel like a million dollars.” These are both
examples of verbal irony.
Irony is also often confused with sarcasm. The two are similar, but in
sarcasm there is an intent to ridicule or mock, often harshly or
crudely.
Dramatic irony is inherent in speeches or a drama and is understood by
the audience, but not grasped by the characters in the play.