This is used quite often in conversational English, when speakers use words that seem to contradict what they are saying.
When a car breaks down, for example, a driver might say any of these:
Fan - tastic.
All of these, in this context, really mean:
In a similar vein, these are rather common as well:
- Yeah, right. (When we don't believe what someone is saying)
- That's bad! (This one is rather dated, but there are contexts when this means something is excellent)
- No way! (When we are astonished by what we just heard)
This is why context is so important in interpreting the meaning of words. Most of the time, when people use words or expressions this way, it's evident – by the circumstances or the tone used by the speaker – that the speaker means the opposite of the literal interpretation of the words they are saying.