Here is what wikipedia has to say on the matter – that may provide some clarity…
Modern theories of rhetoric distinguish between verbal, dramatic and situational irony.
- Verbal irony is a disparity of expression and intention: when a speaker says one thing but means another, or when a literal meaning is contrary to its intended effect. An example of this is sarcasm.
- Dramatic irony is a disparity of expression and awareness: when words and actions possess a significance that the listener or audience understands, but the speaker or character does not.
- Situational irony is the disparity of intention and result: when the result of an action is contrary to the desired or expected effect. Likewise, cosmic irony is disparity between human desires and the harsh realities of the outside world (or the whims of the gods). By some definitions, situational irony and cosmic irony are not irony at all.
And in case you’re confused between sarcasm and verbal irony – because both have the same functional definition – here’s a helpful contrast.
Ridicule is an important aspect of sarcasm, but not verbal irony in general.