Humbug is deceptive nonsense or a fraud meant to trick people. When someone calls something humbug, they're saying it's fake, misleading, or just plain ridiculous. The word carries a sense of impatience or annoyance at being fooled.

You might recognize the word from Charles Dickens's A Christmas Carol, where the grumpy Ebenezer Scrooge repeatedly shouts “Bah! Humbug!” at anything cheerful or Christmas-related. Scrooge thinks Christmas joy is fake and meaningless, just empty sentiment designed to separate people from their money.

A humbug can also be a person who deceives others. A traveling salesman selling fake medicine in the Old West would be called a humbug, promising miracle cures that were really just colored water. When someone claims they can teach you to speak fluent French in one week, or promises that a magic rock will bring you good luck, you might reasonably call those claims humbug.

The word has a wonderful, sputtering sound to it, perfect for expressing indignation when someone tries to fool you. It suggests not just that something is false, but that the whole business is rather ridiculous and deserves to be called out.