A: Your kids are starting school soon. Have you decided what to do next?

B: Moving back to the States is certainly a possibility — I wouldn’t dismiss it out of hand.

Note: In this context, the idiom means “at once, immediately, without due discussion or consideration.” The origin of “off the hand” is unclear, but the idiom evokes the image of a magician producing a card “out of hand,” in the same way that a magician effortlessly produces a pigeon “off the cuff,” meaning almost the same.