Thadius is a distinctive boys' name in United States, ranking #6044 in 2002 with 12 recorded births. The name reached its all-time peak in 1998 with 14 births ranking #4847. Since 1996, the popularity has increased by 20.0%. In 2002, approximately 1 in every 161,789 boys born was named Thadius. RISING Recent data shows the name is currently rising.