Mah-jongg (spelled with one or two gs) is a game of Chinese origin in which players try to create winning hands from a set of domino-like tiles.
The game was imported to the U.S. after World War I by Joseph P. Babcock, who also coined (and trademarked) the name. The game's Chinese name, which sounds similar to "mah-jongg," means "sparrow." A sparrow or a mythical "bird of 100 intelligences" appears on one of the tiles.
Mah-jongg became a fad in the 1920s, but Babcock was more interested in promoting the game than in protecting his trademark, and mah-jongg became a generic term.
In the U.S., the game enjoys periodic revivals, but has never regained its early popularity. In China, it's still widely played.