Thelonious is a distinctive boys' name in United States, ranking #6260 in 1998 with 10 recorded births. The name reached its all-time peak in 2017 with 23 births ranking #4448. Since 1996, the popularity has increased by 66.7%. In 1998, approximately 1 in every 191,132 boys born was named Thelonious. STABLE Recent data shows the name is currently stable.