Rocko is a distinctive boys' name in United States, ranking #12841 in 2004 with 5 recorded births. This places Rocko in the bottom 3% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2014 with 22 births ranking #4506. In 2004, approximately 1 in every 396,960 boys born was named Rocko. STABLE Recent data shows the name is currently stable.