Dream of the Rarebit Fiend is a newspaper comic strip by American cartoonist Winsor McCay, begun September 10, 1904. It was McCay's second successful strip, after Little Sammy Sneeze secured him a position on the cartoon staff of the New York Herald. Rarebit Fiend appeared in the Evening Telegram, a newspaper published by the Herald. For contractual reasons, McCay signed the strip with the pen name "Silas".
The strip had no continuity or recurring characters, but a recurring theme: a character has a nightmare or other bizarre dream, usually after eating a Welsh rarebit—a cheese-on-toast dish. The character awakens in the closing panel and regrets having eaten the rarebit. The dreams often reveal unflattering sides of the dreamers' psyches—their phobias, hypocrisies, discomforts, and dark fantasies. This was in great contrast to the colorful fantasy dreams in McCay's signature strip Little Nemo, which he began in 1905. Whereas children were Nemo's target audience, McCay aimed Rarebit Fiend at adults.