Alan Reed, the original voice of Fred Flintstone, came up with the term ad lib during an early recording session for the series; as Joseph Barbera recalls it in his 1994 memoir My Life In Toons, Reed noted that the script called for him to say simply "Yahoo!", but felt that "Yabba-dabba-doo!" might make it more interesting.
Some sources contend that the term was inspired by the Abba-Zaba bar, a peanut-butter-and-Turkish-taffy sandwich such long popular in the American West.
A variant on the original expression is "Yabba-dabba-doozy!", originating with The Pebbles and Bamm-Bamm Show on CBS in the 1971-72 season and used by a teenage Pebbles in much the same spirit as the original term. Such was also heard in its later spinoffs of The Flintstones Comedy Hour and The Flintstones Comedy Show, as aired on CBS in the 1972-74 period.
The Bedrock Rockers also had a song with that title, the video occasionally featured on both shows as above.