a name given in the past to part of southeast Asia by Europeans. During the 19th century, Indochina included Vietnam, Cambodia, Myanmar, Thailand, Malaysia, and Laos, but in the 20th century Indochina came to mean the countries ruled by France: Vietnam, Cambodia, and Laos. These three countries were also called French Indochina. or Indochinese Peninsula Region of mainland Southeast Asia. The term, now largely superseded by the name Southeast Asia, was used mainly by Westerners to describe the intermingling of Indian and Chinese cultural influences in the region. Indochinese Peninsula typically referred to Cambodia, Laos, and Vietnam (see French Indochina), though it was sometimes expanded to include Myanmar (Burma), Thailand, and the mainland portion of Malaysia