expression, noun
irony of fate; twist of fate
Used when events turn out in a way that is contrary to what was expected, often with a sense of cruel or poetic justice.
彼が事故に遭ったのは運命の皮肉だ。
It's an irony of fate that he had an accident.
運命の皮肉で、彼女は自分の誕生日に解雇された。
By a twist of fate, she was fired on her own birthday.
Compound of 運命 (fate) + の (possessive particle) + 皮肉 (irony). The phrase is a straightforward combination of its parts.