expression, godan verb (-u)
Used to dismiss overly optimistic future plans or predictions as something that even a demon would laugh at. Often appears in the full proverb 来年のことを言うと鬼が笑う (speaking of next year makes the demon laugh).
See also: 来年のことを言うと鬼が笑う
Speaking of next year makes the demon laugh, so let's first do what we can now.
そんな先の計画を立てても鬼が笑うだけだ。
Making plans that far ahead will only make the demon laugh.