ironic

adj. characterized by irony, sarcastic, ironical

Irony is a literary or rhetorical device, in which there is a gap or incongruity between what a speaker or a writer says and what is generally understood (either at the time, or in the later context of history). Irony may also arise from a discordance between acts and results, especially if it is striking, and seen by an outside audience. Irony is understood as an aesthetic evaluation by an audience, which relies on a sharp discordance between the real and the ideal, and which is variously applied to texts, speech, events, acts, and even fashion. All the different senses of irony revolve around the perceived notion of an incongruity, or a gap between an understanding of reality, or expectation of a reality, and what actually happens.
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Adjective
1. humorously sarcastic or mocking; "dry humor"; "an ironic remark often conveys an intended meaning obliquely"; "an ironic novel"; "an ironical smile"; "with a wry Scottish wit"
(synonym) dry, ironical, wry
(similar) humorous, humourous
2. characterized by often poignant difference or incongruity between what is expected and what actually is; "madness, an ironic fate for such a clear thinker"; "it was ironical that the well-planned scheme failed so completely"
(synonym) ironical
(similar) incongruous

(a.)
Ironical.
  

ironic(al) ironically