The noun irony is a form of humour where something is expressed or said but the opposite of it is meant.
Synonyms are humour, paradox, satire or wit.
The word origins from Latin (1500) ironia and from Greek eironeia “dissimulation, assumed ignorance”. It was used in Greek of affected ignorance, especially that of Socrates. Therefore in English it is sometimes used as “simulated ignorance”. Today the word is also applied for events that are curious or coincidental.
Tom has a great sense of irony.
The story was told with humour and sharp irony.
Nobody saw the irony of his story other than me.