expression
delusion; trick of the imagination; momentary lapse of reason
Used when one's judgment is temporarily clouded by emotion or confusion, leading to a mistaken belief or poor decision. Often implies a fleeting, irrational state.
See also: 気迷い
あんなことを言ったのは気の迷いだった。
Saying that was a momentary lapse of reason.
彼女が幽霊を見たと言うのは、気の迷いだろう。
Her claim of seeing a ghost is probably a trick of the imagination.