What do these terms mean?

A dilemma (Greek δί-λημμα “double proposition”) is a problem offering at least two solutions or possibilities, of which none are practically acceptable; one in this position has been traditionally described as being impaled on the horns of a dilemma, neither horn being comfortable

Irony is a literary or rhetorical device, in which there is an incongruity or discordance between what one says or does, and what one means or what is generally understood.

In modern usage, it can refer to incongruity between the intended meaning of an action and the actual or perceived meaning of an action.

There is some argument about what is or is not ironic, but all the different senses of irony revolve around the perceived notion of an incongruity between what is said and what is meant; or between an understanding of reality, or an expectation of a reality, and what actually happens.

next time just look it up online