Irony

"Irony" came into English in the 16^th century from the Latin ironia, which came from the Greek eironeia (simulated ignorance), which came from the Greek eiron (dissembler). The eiron was a type, especially in Aristophanic comedy, which often used a contrast between eiron and alazon (imposter) to dramatize the difference between one who tries to give the appearance of being more than he is (the alazon) and (the eiron), who is more than he appears. This conflict between appearance and reality is the heart of the extended concept of irony that has since developed.

In general, irony is the use of language to express both a surface meaning and a different underlying meaning. There are many different forms of irony, some of which are given below.

1. This category consists of those forms in which there are two audiences: an uninitiated audience, which understands only the surface meaning of the expression; and a privileged audience, or inner circle, which understands both meanings and is aware that the uninitiated audience does not understand. Typically, the speaker addresses the uninitiated audience while the privileged audience observes.
a) Socratic irony is a profession of ignorance. Socrates asked apparently simple, silly questions as a means of discovering whether the accepted wisdom of his time was based on sound principles. The "wise" men he questioned were under the impression that he was an ignorant simpleton, but their attempts to enlighten him served only to expose their own, even greater ignorance. Observers familiar with the technique knew what Socrates was up to, and that those he engaged with hisß questions did not.
b) Dramatic irony is the awareness by a play's audience of the fate in store for a character that is not known to the character himself. In Greek tragedies, for example, certain words seem innocuous and unimportant to the character they concern, but the audience is aware of a meaning of far greater significance and that the character's unawareness will have tragic consequences.
c) The irony of Fate is figurative irony in which an event or a set of circumstances takes the place of the expression of language. A situation that appears to have arisen naturally (i.e., in the normal or natural course of events) is sometimes of such a character that it can be more satisfactorily explained as an act of malice or mischief by Fate, i.e., an act of interference that on the surface was a natural occurrence. The obvious candidates are situations that are particularly perverse, or that seem to mock the expectations of most of us that the course of events will stay within reasonable bounds, or that are humorous at our expense.

2. Verbal irony or rhetorical irony is the use of language to express a surface meaning and a different, usually intended, underlying meaning. This is the common classification for irony that is used simply to express oneself, usually to a single audience, though the term could be correctly applied more broadly (e.g., to Socratic irony, which is a rhetorical means to an end).

Dictionaries often state that the apparent and intended meanings are opposite to each other. Opposite meanings are the most common, and they are often the most effective, but they aren't a requirement. What matters is the audience's recognition and appreciation of the usually sharp contrast between what was said and what was meant, regardless of exactly how the two meanings relate to each other.

Rhetorical irony can be quite sophisticated (e.g., a novel or film might contain a subtle, underlying meaning that only some in the audience detect), but it is most common in its simplest forms in ordinary conversations. Here are some examples of ironic expressions and their underlying meanings.

References:
R1. Fowler, H.W. A Dictionary of Modern English Usage, 1^st Edition (Oxford University Press, 1926)
R2. McArthur, Tom. The Oxford Companion To The English Language (Oxford University Press, 1992)
R3. Concise Oxford Dictionary, UK 8^th Edition (Oxford University Press, 1990)